21723

Appears in sequences

• Numbers whose base-7 representation contains exactly four 2's.at n=32A043404
• Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1100-0100-1111 pattern in any orientation.at n=16A146654
• a(n) = Sum_{i=1..n-1}(i^(n-2)) mod n^4.at n=21A284760
• Triangle read by rows: T(n,r), 0 <= r <= n, is the number of idempotents of rank r in the twisted planar partition monoid PP_n^tau.at n=31A289620
• Sum of the second largest parts in the partitions of n into 5 parts.at n=46A308826
• Triangle T(n,k) (n >= 1, 0 <= k <= n-1) read by rows: number of distinct permutations after k steps of the "first transposition" algorithm.at n=39A345462
• Table read by rows: T(n, k) = T(n, k-1) + m * T(n-1, n-k) for k > 1, T(n, 1) = T(n-1, n-1), and T(n, 0) = 0^n, for m = 2.at n=41A385895