A178846 Number of permutations of 3..n+2 with no element divisible by an adjacent element.

1, 2, 6, 12, 72, 336, 1824, 13152, 134880, 649296, 8572800, 102194400, 1033046880, 12143232960, 210042192960, 2372176649280, 46447968686400, 648516678024960

Offset

1,2

Links

Table of n, a(n) for n=1..18.

Crossrefs

Sequence in context: A287142 A076220 A258213 * A173843 A107763 A166470

Adjacent sequences: A178843 A178844 A178845 * A178847 A178848 A178849

Keyword

nonn

Author

R. H. Hardin Jun 17 2010

Status

approved