61731

Appears in sequences

• Restricted partitions.at n=20A001981
• Numbers n such that n divides 2^n + 1.at n=22A006521
• Number of 3-voter voting schemes with n linearly ranked choices.at n=35A007009
• Numbers k such that k | 8^k + 1.at n=27A015955
• Pseudo-powers to base 3: numbers k that are not powers of 3 such that k divides 2^k + 1.at n=11A016057
• Primitive pseudo-powers to base 3.at n=3A016058
• a(n) = n^2*binomial(n,2).at n=18A092364
• Numbers n such that n divides 2^n^2 + 1.at n=30A093546
• Numbers k that divide 2^(k^3) + 1.at n=31A093665
• Triangle read by rows: T(n,m) = Prime[m]^n*(Prime[m] - 1)/2.at n=30A121057
• a(n) = (prime(n)^4 - prime(n)^3)/2.at n=7A138423
• 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, -1), (-1, -1, 0), (-1, 0, 0), (0, -1, 1), (1, 1, 0)}.at n=10A149118
• Number of nondecreasing arrangements of n numbers in -(n+2)..(n+2) with sum zero.at n=7A188206
• Number of nondecreasing arrangements of 8 numbers in -(n+6)..(n+6) with sum zero.at n=3A188214
• Strong Achilles numbers: Achilles numbers m such that phi(m) is also an Achilles number, where phi(m) denotes Euler's totient function of m.at n=24A194085
• T(n,k)=Petersen graph (3,1) coloring a rectangular array: number of nXk 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0.at n=18A223556
• Petersen graph (3,1) coloring a rectangular array: number of 4Xn 0..5 arrays where 0..5 label nodes of a graph with edges 0,1 0,3 3,5 3,4 1,2 1,4 4,5 2,0 2,5 and every array movement to a horizontal or antidiagonal neighbor moves along an edge of this graph, with the array starting at 0.at n=2A223559
• Numbers k such that between k and the next prime there are gpf(k) numbers, where gpf(k) denotes the largest prime factor of k.at n=36A235425
• Irregular triangle read by rows: T(n, k) = number of inequivalent (mod the dihedral group D_8 of order 8) ways to place k nonattacking knights on an n X n board.at n=37A243716
• a(n) = 9*n^3.at n=19A244728