ΑΡΙΘΜΟΙ 9002 - 9999
9002 is a value of n so that n(n+7) is a palindrome.
9005 is the number of inequivalent Ferrers graphs with 36 points.
9006 is a strobogrammatic number.
9009 is a centered cube number.
9011 has a square that is the concatenation of two consecutive odd numbers.
9012 is the sum of its proper divisors that contain the digit 5.
9016 is the number of perfect squared rectangles of order 16.
9018 has a square with the last 3 digits the same as the 3 digits before that.
9020 is the number of ways to color the vertices of a triangle with 30 colors, up to rotation.
9023 has the property that the concatenation of its prime factors in increasing order is a square.
9024 is the number of regions formed when all diagonals are drawn in a regular 24-gon.
9025 is a Friedman number.
9028 is the number of ways to tile a 9×4 rectangle with integer-sided squares.
9032 would be prime if preceded and followed by a 1, 3, 7, or 9.
9036 has a 9th power that contains the same digits as 358510.
9037 is a value of n for which 2n and 7n together use each digit exactly once.
9038 is the number of conjugacy classes of the alternating group A36.
9042 is the trinomial coefficient T(11,4).
9045 is the number of ways to 18-color the faces of a tetrahedron.
9048 is the number of regions the complex plane is cut into by drawing lines between all pairs of 24th roots of unity.
9049 is an Eisenstein-Mersenne prime.
9052 is the maximum number of regions space can be divided into by 31 spheres.
9055 is the index of a triangular number containing only 3 different digits.
9056 is a cubic star number.
9059 has an 8th root that starts 3.12345....
9070 has a 4th root whose decimal part starts with the digits 1-9 in some order.
9072 has a base 2 and base 3 representation that end with its base 6 representation.
9073 has a base 2 and base 3 representation that end with its base 6 representation.
9074 has a base 3 representation that ends with its base 6 representation.
9077 is a Markov number.
9078 has a cube whose digits occur with the same frequency.
9079 has a square that is the concatenation of two consecutive decreasing numbers.
9086 is the number of regions formed when all diagonals are drawn in a regular 23-gon.
9091 is the only prime known whose reciprocal has period 10.
9093 has a square with the first 3 digits the same as the next 3 digits.
9099 is the number of ways to 3-color the faces of a dodecahedron.
9101 has a square where the first 6 digits alternate.
9104 has a square with the first 3 digits the same as the next 3 digits.
9105 is the number of possible positions in Checkers after 6 moves.
9108 is a heptagonal pyramidal number.
9109 is the number of regions the complex plane is cut into by drawing lines between all pairs of 23rd roots of unity.
9113 is a narcissistic number in base 5.
9115 has a base 3 representation that begins with its base 6 representation.
9116 is a strobogrammatic number.
9117 is a value of n for which 6n and 7n together use each digit exactly once.
9119 is the number of symmetric plane partitions of 34.
9121 is the number of possibilities for the last 5 digits of a square.
9126 is a pentagonal pyramidal number.
9134 has a 10th root whose decimal part starts with the digits 1-9 in some order.
9135 is a value of n for which 2n and 7n together use each digit exactly once.
9137 has a 4th power that is the sum of four 4th powers.
9138 is the number of 13-iamonds without bilateral symmetry.
9139 = 39C3.
9152 and its successor are both divisible by 4th powers.
9153 is a value of n for which 2n and 3n together use each digit exactly once.
9154 is a value of n for which φ(n) and σ(n) are square.
9156 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9158 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9162 is a value of n for which 5n and 8n together use each digit exactly once.
9168 = 27504 / 3, and each digit is contained in the equation exactly once.
9172 is the number of connected planar maps with 7 edges.
9174 is the sum of its proper divisors that contain the digit 5.
9176 is the maximum number of pieces a torus can be cut into with 37 cuts.
9178 is the maximum number of regions a cube can be cut into with 38 cuts.
9179 is a value of n for which φ(n) = φ(n-1) + φ(n-2).
9182 is a value of n for which 4n and 5n together use each digit exactly once.
9183 is the number of sets of distinct positive integers with mean 8.
9185 is a value of n for which 2n and 7n together use each digit exactly once.
9189 is the number of sided 10-ominoes.
9191 is not the sum of a square, a cube, a 4th power, and a 5th power.
9196 has the property that dropping its first and last digits gives its largest prime factor.
9198 is the number of ternary square-free words of length 25.
9201 is a truncated octahedral number.
9214 is the number of ways to stack 30 pennies in contiguous rows so that each penny lies on the table or on two pennies.
9216 is a Friedman number.
9217 is the total number of digits of all binary numbers of length 1-10.
9219 is a value of n for which |cos(n)| is smaller than any previous integer.
9224 is an octahedral number.
9233 is the number of different arrangements (up to rotation and reflection) of 13 non-attacking queens on a 13×13 chessboard.
9234 is the number of multigraphs with 7 vertices and 10 edges.
9235 is the number of 13-iamonds.
9237 is a value of n for which n and 5n together use each digit 1-9 exactly once.
9240 = 22P3.
9241 is a Cuban prime.
9243 has a 4th power that is the sum of four 4th powers.
9248 is the number of possible rook moves on a 17×17 chessboard.
9250 = (103 + 104 + 105 + 106) / (3 × 4 × 5 × 6).
9251 has a square whose digits each occur twice.
9252 is the number of necklaces with 10 white and 10 black beads.
9253 is the smallest number that appears in its factorial 9 times.
9261 is a Friedman number.
9267 is a value of n for which n and 2n together use each digit 1-9 exactly once.
9268 is a value of n for which 2φ(n) = φ(n+1).
9272 is a weird number.
9273 is a value of n for which n and 2n together use each digit 1-9 exactly once.
9282 is the product of three consecutive Fibonacci numbers.
9284 is the number of ways to place 2 non-attacking bishops on a 12×12 chessboard.
9285 is the number of 16-hexes with reflectional symmetry.
9286 is a narcissistic number in base 7.
9287 is the number of stretched 10-ominoes.
9288 can be written as the sum of 2, 3, 4, or 5 positive cubes.
9289 is a Tetranacci-like number starting from 1, 1, 1, and 1.
9296 is the number of ways to break {1,2,3, . . . ,17} into sets with equal sums.
9298 has the property that the concatenation of its prime factors in increasing order is a square.
9304 = 65128 / 7, and each digit is contained in the equation exactly once.
9305 has the property that if each digit is replaced by its square, the resulting number is a square.
9306 is a value of n for which 3n and 5n together use each digit exactly once.
9310 is a decagonal pyramidal number.
9311 is the index of a prime Fibonacci number.
9313, when followed by any of its digits, is prime.
9314 is the 13th Iccanobif number.
9315 is a value of n for which 2n and 3n together use each digit exactly once.
9316 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9321 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9324 is the reciprocal of the sum of the reciprocals of 14652 and its reverse.
9327 is a value of n for which n and 2n together use each digit 1-9 exactly once.
9330 is the Stirling number of the second kind S(10,3).
9331 has the property that the sum of its prime factors is equal to the product of its digits.
9339 is a value of n for which φ(n) = φ(n-2) - φ(n-1).
9347 is a value of n for which the sum of square-free divisors of n and n+1 are the same.
9348 has a 8th power that contains the same digits as 35889.
9349 is the 19th Lucas number.
9350 appears inside its 4th power.
9352 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9360 is a value of n for which σ(n-1) = σ(n+1).
9362 = 22222 in base 8.
9363 is the number of tilted rectangles with vertices in a 15×15 grid.
9364 is the number of connected digraphs with 5 vertices.
9367 is a value of n for which n, n+1, n+2, and n+3 have the same number of divisors.
9371 is a prime that remains prime when preceded and followed by one, two, three, or four 3's.
9374 is a value of n for which φ(σ(n)) = φ(n).
9375 has a cube that ends with those digits.
9376 is an automorphic number.
9377 is a value of n for which n, 2n, 3n, and 4n all use the same number of digits in Roman numerals.
9378 is a value of n for which 4n and 5n together use each digit exactly once.
9380 is the number of lines through exactly 2 points of a 15×15 grid of points.
9382 is a value of n for which 4n and 5n together use each digit exactly once.
9383 is the index of a Fibonacci number whose first 9 digits are the digits 1-9 rearranged.
9385 is the sum of consecutive squares in 2 ways.
9386 = 99 + 333 + 8888 + 66.
9387 is a Smith brother.
9391 has a square with the first 3 digits the same as the last 3 digits.
9393 is the number of non-isomorphic 3×3×3 Rubik's cube positions that require exactly 5 quarter turns to solve.
9394 is a value of n so that n(n+8) is a palindrome.
9396 is the number of symmetric 3×3 matrices in base 6 with determinant 0.
9403 = 65821 / 7, and each digit is contained in the equation exactly once.
9406 is the index of a triangular number containing only 3 different digits.
9407 has a 7th root whose decimal part starts with the digits 1-9 in some order.
9408 is the number of reduced 6×6 Latin squares.
9413 has a cube whose digits occur with the same frequency.
9415 is the sum of the first 19 numbers that have digit sum 19.
9416 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9421 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9424 has the property that the fractional part of π9424 begins .9424....
9426 is a value of n for which 5n and 7n together use each digit exactly once.
9427 is the smallest number that can not be formed using the digit 1 at most 29 times, together with the symbols +, –, × and ÷.
9428 is the smallest number whose square begins with four 8's.
9431 is a number n for which n, n+2, n+6, and n+8 are all prime.
9432 is the number of 3-colored rooted trees with 6 vertices.
9436 is the smallest number whose 15th power contains exactly the same digits as another 15th power.
9439 is prime, and 5 closest primes are all smaller.
9444 has a square with the first 3 digits the same as the next 3 digits.
9445 is the closest integer to 29e.
9450 is the denominator of ζ(8) / π8.
9451 is the number of binary rooted trees with 19 vertices.
9452 is the smallest number whose cube contains 5 consecutive 4's.
9455 is the sum of the first 30 squares.
9465 is an hexagonal prism number.
9468 is the sum of its proper divisors that contain the digit 7.
9471 is an octagonal pyramidal number.
9473 is a Proth prime.
9474 is a narcissistic number.
9477 is the maximum determinant of a binary 13×13 matrix.
9481 is a number whose sum of divisors is a 4th power.
9489 is the closest integer to π8.
9493 is a member of the Fibonacci-type sequence starting with 1 and 9.
9496 is the number of 10×10 symmetric permutation matrices.
9497 is the number of bicentered trees with 16 vertices.
9499 has a 5th power whose first few digits are 77337377....
9500 is a hexagonal pyramidal number.
9504 is a betrothed number.
9513 is the smallest number without increasing digits that is divisible by the number formed by writing its digits in increasing order.
9519 has a 4th power that is the sum of four 4th powers.
9520 is an enneagonal pyramidal number.
9523 is a value of n for which 4n and 5n together use each digit exactly once.
9529 is the number of 3×3 sliding puzzle positions that require exactly 18 moves to solve starting with the hole in a corner.
9531 is the index of a prime Woodall number.
9538 is a value of n for which 4n and 5n together use each digit exactly once.
9541 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9542 is the number of ways to place a non-attacking white and black pawn on a 11×11 chessboard.
9545 is a number with the property that the root-mean-square of its divisors is an integer.
9551 has the same digits as the 9551st prime.
9552 and the following 34 numbers are composite.
9555 is an odd primitive abundant number.
9563 = 9 + 5555 + 666 + 3333.
9564 is the number of paraffins with 10 carbon atoms.
9568 = 9 + 5 + 666 + 8888.
9574 is a value of n for which |cos(n)| is smaller than any previous integer.
9576 = 19!!!!!.
9583 is the number of subsets of {1, 2, 3, ... 20} that do not contain solutions to x + y = z.
9592 is the number of primes with 5 or fewer digits.
9596 is the index of a triangular number containing only 3 different digits.
9601 is a Proth prime.
9602 has the property that if each digit is replaced by its square, the resulting number is a square.
9605, when concatenated with 4 less than itself, is square.
9608 is the number of digraphs with 5 vertices.
9615 is the smallest number whose cube starts with 5 identical digits.
9616 is an icosahedral number.
9623 is the number of symmetric 10-cubes.
9625 has a square formed by inserting a block of digits inside itself.
9627 is a value of n for which n and 5n together use each digit 1-9 exactly once.
9629 is a value of n for which 2n and 7n together use each digit exactly once.
9632 is the number of different arrangements of 4 non-attacking queens on a 4×14 chessboard.
9633 is a Smith brother.
9634 is a Smith brother.
9639 has a 4th power that is the sum of four 4th powers.
9643 is the smallest number that can not be formed using the numbers 20, 21, ... , 27, together with the symbols +, –, × and ÷.
9648 is a factor of the sum of the digits of 96489648.
9653 = 99 + 666 + 5555 + 3333.
9658 = 99 + 666 + 5 + 8888.
9660 is a truncated tetrahedral number.
9670 is the number of 8-digit triangular numbers.
9673 is the number of triangles of any size contained in the triangle of side 33 on a triangular grid.
9677 is a prime that remains prime if any digit is deleted.
9682 is a value of n for which n!! - 1 is prime.
9689 is the exponent of a Mersenne prime.
9691 has the property that the concatenation of its prime factors in increasing order is a square.
9695 is the sum of the digits of 555.
9696 is a strobogrammatic number.
9700 is the number of inequivalent 4-digit strings, where two strings are equivalent if turning one upside down gives the other.
9701 has a square whose digits each occur twice.
9707 does not occur in its factorial in base 2.
9709 has a cube whose digits occur with the same frequency.
9711 uses the same digits as π(9711).
9716 is the number of Pyramorphix puzzle positions that require exactly 5 moves to solve.
9720 is the order of a perfect group.
9721 is the largest prime factor of 1234567.
9723 is a value of n for which n and 5n together use each digit 1-9 exactly once.
9724 = 1111 in base 21.
9726 is the smallest number in base 5 whose square contains the same digits in the same proportion.
9728 can be written as the sum of 2, 3, 4, or 5 positive cubes.
9738 is the number of trees on 22 vertices with diameter 5.
9747 is an Achilles number.
9748 is the maximum value of n so that there exist 6 denominations of stamps so that every postage from 1 to n can be paid for with at most 14 stamps.
9751 is the number of possible configurations of pegs (up to symmetry) after 8 jumps in solitaire.
9753 is a value of n for which 4n and 5n together use each digit exactly once.
9754 is the number of paths between opposite corners of a 3×5 rectangle graph.
9760 can be written as the product of a number and its reverse in 2 different ways.
9764 would be prime if preceded and followed by a 1, 3, 7, or 9.
9765 is an odd primitive abundant number.
9767 is the largest 4 digit prime composed of concatenating two 2 digit primes.
9768 = 2 × 22 × 222.
9770 is the number of Hamiltonian cycles of a 4×12 rectangle graph.
9775 is a number n so that the sum of the digits of nn-1 is divisible by n.
9777 is the number of graphs on 8 vertices with no isolated vertices.
9779 has a square root that has four 8's immediately after the decimal point.
9784 is the number of 2 state Turing machines which halt.
9786 has a square whose digits each occur twice.
9789 is the smallest number that appears in its factorial 11 times.
9790 is the number of ways to place 2 non-attacking kings on a 12×12 chessboard.
9792 is the number of partitions of 59 into distinct parts.
9793 is the smallest number that can be written as the sum of 4 distinct positive cubes in 5 ways.
9796 has the property that dropping its first and last digits gives its largest prime factor.
9797 is the product of two consecutive primes.
9798 is a number whose sum of divisors is a 4th power.
9799 is a number with the property that the root-mean-square of its divisors is an integer.
9800 is the largest 4-digit number with single digit prime factors.
9801 is 9 times its reverse.
9802, when concatenated with one less than it, is square.
9803 is the number of different degree sequences possible for a graph with 19 edges.
9805 is the number of subsequences of {1,2,3,...15} in which every odd number has an even neighbor.
9809 is a stella octangula number.
9823 is the number of centered trees with 16 vertices.
9824 is a structured snub cubic number.
9828 is the order of a non-cyclic simple group.
9831 has a base 6 representation which is the reverse of its base 5 representation.
9839 would be prime if preceded and followed by a 1, 3, 7, or 9.
9841 = 111111111 in base 3.
9843 is the number of vertices in a Sierpinski triangle of order 8.
9849 is a centered tetrahedral number.
9854 is the index of a triangular number containing only 3 different digits.
9855 is a rhombic dodecahedral number.
9856 is the number of ways to place 2 non-attacking knights on a 12×12 chessboard.
9857 is a Proth prime.
9858 is a number whose sum of divisors is a 4th power.
9861 is a dodecagonal pyramidal number.
9862 is the number of knight's tours on a 6×6 chessboard.
9865 is the number of digits in the 15th Fermat number.
9868 is the number of hydrocarbons with 10 carbon atoms.
9871 is the largest 4-digit prime with different digits.
9872 = 8 + 88 + 888 + 8888.
9876 is the largest 4-digit number with different digits.
9877 has a 4th power that is the sum of four 4th powers.
9878 has a 10th power whose first few digits are 88448448....
9880 = 40C3.
9886 is a strobogrammatic number.
9888 is the number of connected graphs with 8 vertices whose complements are also connected.
9894 is the number of 3-colored trees with 7 vertices.
9896 is the number of Pyraminx puzzle positions that require exactly 6 moves to solve.
9900 = 100110101011002 = 990010 = 188119 = 119921, each using two digits the same number of times.
9901 is the only prime known whose reciprocal has period 12.
9910 is the number of fixed 9-ominoes.
9911 has the property that the sum of its prime factors is equal to the product of its digits.
9912 is the number of graceful permutations of length 14.
9913, when followed by any of its digits, is prime.
9918 is the maximum number of pieces a torus can be cut into with 38 cuts.
9919 can be written as the difference between two positive cubes in more than one way.
9920 is the maximum number of regions a cube can be cut into with 39 cuts.
9928 is a value of n for which reverse(φ(n)) = φ(reverse(n)).
9929 is the number of 3×3 sliding puzzle positions that require exactly 26 moves to solve starting with the hole on a side.
9933 = 441 + 442 + . . . + 462 = 463 + 464 + . . . + 483.
9941 is the exponent of a Mersenne prime.
9944 = 100110110110002 = 994410 = 2E2E15 = 11BB21, each using two digits the same number of times.
9945 = 17!!!!.
9951 is the number of ways to color the vertices of a triangle with 31 colors, up to rotation.
9959 is a member of the Fibonacci-type sequence starting with 2 and 5.
9960 is the number of 3×3×3 sliding puzzle positions that require exactly 8 moves to solve.
9966 is the largest 4-digit strobogrammatic number.
9973 is the largest 4-digit prime.
9976 has a square formed by inserting a block of digits inside itself.
9984 is the maximum number of regions space can be divided into by 32 spheres.
9985 is the number of hyperbolic knots with 13 crossings.
9988 is the number of prime knots with 13 crossings.
9992 is the number of 2×2×2 Rubik's cube positions that require exactly 5 moves to solve.
9995 has a square formed by inserting a block of digits inside itself.
9996 has a square formed by inserting a block of digits inside itself.
9998 is the smallest number n for which the concatenation of n, (n+1), ... (n+21) is prime.
9999 is a Kaprekar number.
9005 is the number of inequivalent Ferrers graphs with 36 points.
9006 is a strobogrammatic number.
9009 is a centered cube number.
9011 has a square that is the concatenation of two consecutive odd numbers.
9012 is the sum of its proper divisors that contain the digit 5.
9016 is the number of perfect squared rectangles of order 16.
9018 has a square with the last 3 digits the same as the 3 digits before that.
9020 is the number of ways to color the vertices of a triangle with 30 colors, up to rotation.
9023 has the property that the concatenation of its prime factors in increasing order is a square.
9024 is the number of regions formed when all diagonals are drawn in a regular 24-gon.
9025 is a Friedman number.
9028 is the number of ways to tile a 9×4 rectangle with integer-sided squares.
9032 would be prime if preceded and followed by a 1, 3, 7, or 9.
9036 has a 9th power that contains the same digits as 358510.
9037 is a value of n for which 2n and 7n together use each digit exactly once.
9038 is the number of conjugacy classes of the alternating group A36.
9042 is the trinomial coefficient T(11,4).
9045 is the number of ways to 18-color the faces of a tetrahedron.
9048 is the number of regions the complex plane is cut into by drawing lines between all pairs of 24th roots of unity.
9049 is an Eisenstein-Mersenne prime.
9052 is the maximum number of regions space can be divided into by 31 spheres.
9055 is the index of a triangular number containing only 3 different digits.
9056 is a cubic star number.
9059 has an 8th root that starts 3.12345....
9070 has a 4th root whose decimal part starts with the digits 1-9 in some order.
9072 has a base 2 and base 3 representation that end with its base 6 representation.
9073 has a base 2 and base 3 representation that end with its base 6 representation.
9074 has a base 3 representation that ends with its base 6 representation.
9077 is a Markov number.
9078 has a cube whose digits occur with the same frequency.
9079 has a square that is the concatenation of two consecutive decreasing numbers.
9086 is the number of regions formed when all diagonals are drawn in a regular 23-gon.
9091 is the only prime known whose reciprocal has period 10.
9093 has a square with the first 3 digits the same as the next 3 digits.
9099 is the number of ways to 3-color the faces of a dodecahedron.
9101 has a square where the first 6 digits alternate.
9104 has a square with the first 3 digits the same as the next 3 digits.
9105 is the number of possible positions in Checkers after 6 moves.
9108 is a heptagonal pyramidal number.
9109 is the number of regions the complex plane is cut into by drawing lines between all pairs of 23rd roots of unity.
9113 is a narcissistic number in base 5.
9115 has a base 3 representation that begins with its base 6 representation.
9116 is a strobogrammatic number.
9117 is a value of n for which 6n and 7n together use each digit exactly once.
9119 is the number of symmetric plane partitions of 34.
9121 is the number of possibilities for the last 5 digits of a square.
9126 is a pentagonal pyramidal number.
9134 has a 10th root whose decimal part starts with the digits 1-9 in some order.
9135 is a value of n for which 2n and 7n together use each digit exactly once.
9137 has a 4th power that is the sum of four 4th powers.
9138 is the number of 13-iamonds without bilateral symmetry.
9139 = 39C3.
9152 and its successor are both divisible by 4th powers.
9153 is a value of n for which 2n and 3n together use each digit exactly once.
9154 is a value of n for which φ(n) and σ(n) are square.
9156 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9158 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9162 is a value of n for which 5n and 8n together use each digit exactly once.
9168 = 27504 / 3, and each digit is contained in the equation exactly once.
9172 is the number of connected planar maps with 7 edges.
9174 is the sum of its proper divisors that contain the digit 5.
9176 is the maximum number of pieces a torus can be cut into with 37 cuts.
9178 is the maximum number of regions a cube can be cut into with 38 cuts.
9179 is a value of n for which φ(n) = φ(n-1) + φ(n-2).
9182 is a value of n for which 4n and 5n together use each digit exactly once.
9183 is the number of sets of distinct positive integers with mean 8.
9185 is a value of n for which 2n and 7n together use each digit exactly once.
9189 is the number of sided 10-ominoes.
9191 is not the sum of a square, a cube, a 4th power, and a 5th power.
9196 has the property that dropping its first and last digits gives its largest prime factor.
9198 is the number of ternary square-free words of length 25.
9201 is a truncated octahedral number.
9214 is the number of ways to stack 30 pennies in contiguous rows so that each penny lies on the table or on two pennies.
9216 is a Friedman number.
9217 is the total number of digits of all binary numbers of length 1-10.
9219 is a value of n for which |cos(n)| is smaller than any previous integer.
9224 is an octahedral number.
9233 is the number of different arrangements (up to rotation and reflection) of 13 non-attacking queens on a 13×13 chessboard.
9234 is the number of multigraphs with 7 vertices and 10 edges.
9235 is the number of 13-iamonds.
9237 is a value of n for which n and 5n together use each digit 1-9 exactly once.
9240 = 22P3.
9241 is a Cuban prime.
9243 has a 4th power that is the sum of four 4th powers.
9248 is the number of possible rook moves on a 17×17 chessboard.
9250 = (103 + 104 + 105 + 106) / (3 × 4 × 5 × 6).
9251 has a square whose digits each occur twice.
9252 is the number of necklaces with 10 white and 10 black beads.
9253 is the smallest number that appears in its factorial 9 times.
9261 is a Friedman number.
9267 is a value of n for which n and 2n together use each digit 1-9 exactly once.
9268 is a value of n for which 2φ(n) = φ(n+1).
9272 is a weird number.
9273 is a value of n for which n and 2n together use each digit 1-9 exactly once.
9282 is the product of three consecutive Fibonacci numbers.
9284 is the number of ways to place 2 non-attacking bishops on a 12×12 chessboard.
9285 is the number of 16-hexes with reflectional symmetry.
9286 is a narcissistic number in base 7.
9287 is the number of stretched 10-ominoes.
9288 can be written as the sum of 2, 3, 4, or 5 positive cubes.
9289 is a Tetranacci-like number starting from 1, 1, 1, and 1.
9296 is the number of ways to break {1,2,3, . . . ,17} into sets with equal sums.
9298 has the property that the concatenation of its prime factors in increasing order is a square.
9304 = 65128 / 7, and each digit is contained in the equation exactly once.
9305 has the property that if each digit is replaced by its square, the resulting number is a square.
9306 is a value of n for which 3n and 5n together use each digit exactly once.
9310 is a decagonal pyramidal number.
9311 is the index of a prime Fibonacci number.
9313, when followed by any of its digits, is prime.
9314 is the 13th Iccanobif number.
9315 is a value of n for which 2n and 3n together use each digit exactly once.
9316 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9321 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9324 is the reciprocal of the sum of the reciprocals of 14652 and its reverse.
9327 is a value of n for which n and 2n together use each digit 1-9 exactly once.
9330 is the Stirling number of the second kind S(10,3).
9331 has the property that the sum of its prime factors is equal to the product of its digits.
9339 is a value of n for which φ(n) = φ(n-2) - φ(n-1).
9347 is a value of n for which the sum of square-free divisors of n and n+1 are the same.
9348 has a 8th power that contains the same digits as 35889.
9349 is the 19th Lucas number.
9350 appears inside its 4th power.
9352 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9360 is a value of n for which σ(n-1) = σ(n+1).
9362 = 22222 in base 8.
9363 is the number of tilted rectangles with vertices in a 15×15 grid.
9364 is the number of connected digraphs with 5 vertices.
9367 is a value of n for which n, n+1, n+2, and n+3 have the same number of divisors.
9371 is a prime that remains prime when preceded and followed by one, two, three, or four 3's.
9374 is a value of n for which φ(σ(n)) = φ(n).
9375 has a cube that ends with those digits.
9376 is an automorphic number.
9377 is a value of n for which n, 2n, 3n, and 4n all use the same number of digits in Roman numerals.
9378 is a value of n for which 4n and 5n together use each digit exactly once.
9380 is the number of lines through exactly 2 points of a 15×15 grid of points.
9382 is a value of n for which 4n and 5n together use each digit exactly once.
9383 is the index of a Fibonacci number whose first 9 digits are the digits 1-9 rearranged.
9385 is the sum of consecutive squares in 2 ways.
9386 = 99 + 333 + 8888 + 66.
9387 is a Smith brother.
9391 has a square with the first 3 digits the same as the last 3 digits.
9393 is the number of non-isomorphic 3×3×3 Rubik's cube positions that require exactly 5 quarter turns to solve.
9394 is a value of n so that n(n+8) is a palindrome.
9396 is the number of symmetric 3×3 matrices in base 6 with determinant 0.
9403 = 65821 / 7, and each digit is contained in the equation exactly once.
9406 is the index of a triangular number containing only 3 different digits.
9407 has a 7th root whose decimal part starts with the digits 1-9 in some order.
9408 is the number of reduced 6×6 Latin squares.
9413 has a cube whose digits occur with the same frequency.
9415 is the sum of the first 19 numbers that have digit sum 19.
9416 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9421 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9424 has the property that the fractional part of π9424 begins .9424....
9426 is a value of n for which 5n and 7n together use each digit exactly once.
9427 is the smallest number that can not be formed using the digit 1 at most 29 times, together with the symbols +, –, × and ÷.
9428 is the smallest number whose square begins with four 8's.
9431 is a number n for which n, n+2, n+6, and n+8 are all prime.
9432 is the number of 3-colored rooted trees with 6 vertices.
9436 is the smallest number whose 15th power contains exactly the same digits as another 15th power.
9439 is prime, and 5 closest primes are all smaller.
9444 has a square with the first 3 digits the same as the next 3 digits.
9445 is the closest integer to 29e.
9450 is the denominator of ζ(8) / π8.
9451 is the number of binary rooted trees with 19 vertices.
9452 is the smallest number whose cube contains 5 consecutive 4's.
9455 is the sum of the first 30 squares.
9465 is an hexagonal prism number.
9468 is the sum of its proper divisors that contain the digit 7.
9471 is an octagonal pyramidal number.
9473 is a Proth prime.
9474 is a narcissistic number.
9477 is the maximum determinant of a binary 13×13 matrix.
9481 is a number whose sum of divisors is a 4th power.
9489 is the closest integer to π8.
9493 is a member of the Fibonacci-type sequence starting with 1 and 9.
9496 is the number of 10×10 symmetric permutation matrices.
9497 is the number of bicentered trees with 16 vertices.
9499 has a 5th power whose first few digits are 77337377....
9500 is a hexagonal pyramidal number.
9504 is a betrothed number.
9513 is the smallest number without increasing digits that is divisible by the number formed by writing its digits in increasing order.
9519 has a 4th power that is the sum of four 4th powers.
9520 is an enneagonal pyramidal number.
9523 is a value of n for which 4n and 5n together use each digit exactly once.
9529 is the number of 3×3 sliding puzzle positions that require exactly 18 moves to solve starting with the hole in a corner.
9531 is the index of a prime Woodall number.
9538 is a value of n for which 4n and 5n together use each digit exactly once.
9541 is a value of n for which n and 8n together use each digit 1-9 exactly once.
9542 is the number of ways to place a non-attacking white and black pawn on a 11×11 chessboard.
9545 is a number with the property that the root-mean-square of its divisors is an integer.
9551 has the same digits as the 9551st prime.
9552 and the following 34 numbers are composite.
9555 is an odd primitive abundant number.
9563 = 9 + 5555 + 666 + 3333.
9564 is the number of paraffins with 10 carbon atoms.
9568 = 9 + 5 + 666 + 8888.
9574 is a value of n for which |cos(n)| is smaller than any previous integer.
9576 = 19!!!!!.
9583 is the number of subsets of {1, 2, 3, ... 20} that do not contain solutions to x + y = z.
9592 is the number of primes with 5 or fewer digits.
9596 is the index of a triangular number containing only 3 different digits.
9601 is a Proth prime.
9602 has the property that if each digit is replaced by its square, the resulting number is a square.
9605, when concatenated with 4 less than itself, is square.
9608 is the number of digraphs with 5 vertices.
9615 is the smallest number whose cube starts with 5 identical digits.
9616 is an icosahedral number.
9623 is the number of symmetric 10-cubes.
9625 has a square formed by inserting a block of digits inside itself.
9627 is a value of n for which n and 5n together use each digit 1-9 exactly once.
9629 is a value of n for which 2n and 7n together use each digit exactly once.
9632 is the number of different arrangements of 4 non-attacking queens on a 4×14 chessboard.
9633 is a Smith brother.
9634 is a Smith brother.
9639 has a 4th power that is the sum of four 4th powers.
9643 is the smallest number that can not be formed using the numbers 20, 21, ... , 27, together with the symbols +, –, × and ÷.
9648 is a factor of the sum of the digits of 96489648.
9653 = 99 + 666 + 5555 + 3333.
9658 = 99 + 666 + 5 + 8888.
9660 is a truncated tetrahedral number.
9670 is the number of 8-digit triangular numbers.
9673 is the number of triangles of any size contained in the triangle of side 33 on a triangular grid.
9677 is a prime that remains prime if any digit is deleted.
9682 is a value of n for which n!! - 1 is prime.
9689 is the exponent of a Mersenne prime.
9691 has the property that the concatenation of its prime factors in increasing order is a square.
9695 is the sum of the digits of 555.
9696 is a strobogrammatic number.
9700 is the number of inequivalent 4-digit strings, where two strings are equivalent if turning one upside down gives the other.
9701 has a square whose digits each occur twice.
9707 does not occur in its factorial in base 2.
9709 has a cube whose digits occur with the same frequency.
9711 uses the same digits as π(9711).
9716 is the number of Pyramorphix puzzle positions that require exactly 5 moves to solve.
9720 is the order of a perfect group.
9721 is the largest prime factor of 1234567.
9723 is a value of n for which n and 5n together use each digit 1-9 exactly once.
9724 = 1111 in base 21.
9726 is the smallest number in base 5 whose square contains the same digits in the same proportion.
9728 can be written as the sum of 2, 3, 4, or 5 positive cubes.
9738 is the number of trees on 22 vertices with diameter 5.
9747 is an Achilles number.
9748 is the maximum value of n so that there exist 6 denominations of stamps so that every postage from 1 to n can be paid for with at most 14 stamps.
9751 is the number of possible configurations of pegs (up to symmetry) after 8 jumps in solitaire.
9753 is a value of n for which 4n and 5n together use each digit exactly once.
9754 is the number of paths between opposite corners of a 3×5 rectangle graph.
9760 can be written as the product of a number and its reverse in 2 different ways.
9764 would be prime if preceded and followed by a 1, 3, 7, or 9.
9765 is an odd primitive abundant number.
9767 is the largest 4 digit prime composed of concatenating two 2 digit primes.
9768 = 2 × 22 × 222.
9770 is the number of Hamiltonian cycles of a 4×12 rectangle graph.
9775 is a number n so that the sum of the digits of nn-1 is divisible by n.
9777 is the number of graphs on 8 vertices with no isolated vertices.
9779 has a square root that has four 8's immediately after the decimal point.
9784 is the number of 2 state Turing machines which halt.
9786 has a square whose digits each occur twice.
9789 is the smallest number that appears in its factorial 11 times.
9790 is the number of ways to place 2 non-attacking kings on a 12×12 chessboard.
9792 is the number of partitions of 59 into distinct parts.
9793 is the smallest number that can be written as the sum of 4 distinct positive cubes in 5 ways.
9796 has the property that dropping its first and last digits gives its largest prime factor.
9797 is the product of two consecutive primes.
9798 is a number whose sum of divisors is a 4th power.
9799 is a number with the property that the root-mean-square of its divisors is an integer.
9800 is the largest 4-digit number with single digit prime factors.
9801 is 9 times its reverse.
9802, when concatenated with one less than it, is square.
9803 is the number of different degree sequences possible for a graph with 19 edges.
9805 is the number of subsequences of {1,2,3,...15} in which every odd number has an even neighbor.
9809 is a stella octangula number.
9823 is the number of centered trees with 16 vertices.
9824 is a structured snub cubic number.
9828 is the order of a non-cyclic simple group.
9831 has a base 6 representation which is the reverse of its base 5 representation.
9839 would be prime if preceded and followed by a 1, 3, 7, or 9.
9841 = 111111111 in base 3.
9843 is the number of vertices in a Sierpinski triangle of order 8.
9849 is a centered tetrahedral number.
9854 is the index of a triangular number containing only 3 different digits.
9855 is a rhombic dodecahedral number.
9856 is the number of ways to place 2 non-attacking knights on a 12×12 chessboard.
9857 is a Proth prime.
9858 is a number whose sum of divisors is a 4th power.
9861 is a dodecagonal pyramidal number.
9862 is the number of knight's tours on a 6×6 chessboard.
9865 is the number of digits in the 15th Fermat number.
9868 is the number of hydrocarbons with 10 carbon atoms.
9871 is the largest 4-digit prime with different digits.
9872 = 8 + 88 + 888 + 8888.
9876 is the largest 4-digit number with different digits.
9877 has a 4th power that is the sum of four 4th powers.
9878 has a 10th power whose first few digits are 88448448....
9880 = 40C3.
9886 is a strobogrammatic number.
9888 is the number of connected graphs with 8 vertices whose complements are also connected.
9894 is the number of 3-colored trees with 7 vertices.
9896 is the number of Pyraminx puzzle positions that require exactly 6 moves to solve.
9900 = 100110101011002 = 990010 = 188119 = 119921, each using two digits the same number of times.
9901 is the only prime known whose reciprocal has period 12.
9910 is the number of fixed 9-ominoes.
9911 has the property that the sum of its prime factors is equal to the product of its digits.
9912 is the number of graceful permutations of length 14.
9913, when followed by any of its digits, is prime.
9918 is the maximum number of pieces a torus can be cut into with 38 cuts.
9919 can be written as the difference between two positive cubes in more than one way.
9920 is the maximum number of regions a cube can be cut into with 39 cuts.
9928 is a value of n for which reverse(φ(n)) = φ(reverse(n)).
9929 is the number of 3×3 sliding puzzle positions that require exactly 26 moves to solve starting with the hole on a side.
9933 = 441 + 442 + . . . + 462 = 463 + 464 + . . . + 483.
9941 is the exponent of a Mersenne prime.
9944 = 100110110110002 = 994410 = 2E2E15 = 11BB21, each using two digits the same number of times.
9945 = 17!!!!.
9951 is the number of ways to color the vertices of a triangle with 31 colors, up to rotation.
9959 is a member of the Fibonacci-type sequence starting with 2 and 5.
9960 is the number of 3×3×3 sliding puzzle positions that require exactly 8 moves to solve.
9966 is the largest 4-digit strobogrammatic number.
9973 is the largest 4-digit prime.
9976 has a square formed by inserting a block of digits inside itself.
9984 is the maximum number of regions space can be divided into by 32 spheres.
9985 is the number of hyperbolic knots with 13 crossings.
9988 is the number of prime knots with 13 crossings.
9992 is the number of 2×2×2 Rubik's cube positions that require exactly 5 moves to solve.
9995 has a square formed by inserting a block of digits inside itself.
9996 has a square formed by inserting a block of digits inside itself.
9998 is the smallest number n for which the concatenation of n, (n+1), ... (n+21) is prime.
9999 is a Kaprekar number.
Excellent Post.
ΑπάντησηΔιαγραφήHi , I am Sanjay Gulati , a mathematics teacher from India.
I have a mathematics blog , please visit it at http://mathematicsbhilai.blogspot.com/.
Please link my blog to your blog.
Sanjay Gulati