31999

Appears in sequences

• Numbers k such that phi(k)+sigma(k) is a perfect cube.at n=21A061366
• Permutation of N induced by rotating the node 3 right in the infinite planar binary tree shown at A065658.at n=55A065664
• Smallest number beginning with n and having a digit sum n.at n=30A077726
• Expansion of (1-x)^(-1)/(1-2*x+2*x^2-2*x^3).at n=22A077858
• Numbers of length n binary words with fewer than 7 0-digits between any pair of consecutive 1-digits.at n=15A145115
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, -1, 1), (-1, 1, -1), (0, 0, 1), (1, 0, 0)}.at n=10A149816
• a(n) = 20*n^2 - 1.at n=39A158491
• a(n) = 80*n^2 - 1.at n=19A158774
• Partial sums of floor(n^3/2).at n=22A173704
• Absolute discriminants of complex quadratic fields with 3-class group of type (3,3) and Hilbert 3-class field tower of exact length 2.at n=16A242864
• Absolute discriminants of complex quadratic fields with 3-class group of type (3,3) and 3-principalization type (4224).at n=7A247690
• Absolute discriminants of complex quadratic fields with 3-class group of type (3,3) whose second 3-class group is located on the sporadic part of the coclass graph G(3,2) outside of coclass trees.at n=23A247691
• Number of (n+1)X(6+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.at n=2A253324
• T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.at n=30A253326
• Number of (3+1)X(n+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.at n=5A253328
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 193", based on the 5-celled von Neumann neighborhood.at n=14A279723
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 449", based on the 5-celled von Neumann neighborhood.at n=14A282268
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 451", based on the 5-celled von Neumann neighborhood.at n=14A282299
• Triangle read by rows: T(n,k) is the number of n-digit numbers having a k-digit greatest prime factor.at n=12A294952
• Numbers k such that the sum of decimal digits of k is the sum of primes dividing k+1 (with repetition).at n=27A339805