A225965 Number of permutations of [n] having exactly 4 strong fixed blocks.

1, 13, 117, 928, 7125, 55527, 451472, 3896347, 36098855, 361638248, 3932908263, 46483325765, 596325240445, 8278698772954, 123863754811374, 1988038987565688, 34070987657660446, 620747700139873322, 11975106447284305656, 243741719070454243530

Offset: 10

Author

Alois P. Heinz, May 22 2013

Keywords

• nonn

Comments

See A186373 for the definition of strong fixed blocks.

Links

• Alois P. Heinz, Table of n, a(n) for n = 10..450

Crossrefs

Column k=4 of A186373.

Formula

a(n) ~ 3 * n! / n^8. - Vaclav Kotesovec, Aug 29 2014