A321050 Number of permutations of [n] with no fixed points where the maximal displacement of an element equals four.

0, 20, 111, 396, 1285, 4312, 15437, 55572, 196288, 678270, 2311191, 7856610, 26732463, 90996552, 309390463, 1049670138, 3554983881, 12027825752, 40676758809, 137534141216, 464908099716, 1571078027012, 5307751810223, 17928124690902, 60548310641344

Offset: 4

Author

Alois P. Heinz, Oct 26 2018

Keywords

• nonn
• easy

Links

• Alois P. Heinz, Table of n, a(n) for n = 4..1000

Crossrefs

Column k=4 of A259784.

Cf. A079997, A259777.

Formula

a(n) = A259777(n) - A079997(n).