56712

Appears in sequences

• Number of n-rowed binary matrices with all row sums 5, up to row and column permutation; bipartite graphs with all nodes of degree 5 in a distinguished bipartite n-block, up to isomorphism.at n=5A058784
• Numbers k such that both k and k^2/2 are averages of twin prime pairs.at n=37A152787
• a(n) = 49*n^2 + 2*n.at n=33A157365
• Numbers n such that product of double factorials of the digits of n equals sigma(n).at n=14A158989
• a(n) is the smallest number not yet in the sequence such that the concatenation of all terms yields a periodic stream of digits 1, 2, 3, ..., 7 (repeat from 1).at n=33A165305
• Numbers k such that in a rotated-square spiral with positive integers (A215468) among k's eight nearest neighbors five or more are primes.at n=23A215471
• Triangle read by rows: T(n,m) is the number of inequivalent n X m matrices under action of the Klein group, with a sixth of 1s, 2s, 3s, 4s, 5s and 6s (ordered occurrences rounded up/down if n*m != 0 mod 6).at n=17A287022
• Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n) - 1, where a(0) = 2, a(1) = 3, b(0) = 1, b(1) = 4, b(2) = 5, and (a(n)) and (b(n)) are increasing complementary sequences.at n=19A295965
• Array read by antidiagonals: A(n,k) is the number of nonequivalent binary matrices with k columns and any number of nonzero rows with n ones in every column up to permutation of rows and columns.at n=60A331461