A177613 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, up, down, down, down

1, 20, 1680, 365824, 163212800, 129754904960, 167412069509691, 327734823220485100

Offset

1,2

Links

Table of n, a(n) for n=1..8.

Crossrefs

Sequence in context: A177612 A177618 A177624 * A177619 A177623 A177633

Adjacent sequences: A177610 A177611 A177612 * A177614 A177615 A177616

Keyword

nonn

Author

R. H. Hardin May 10 2010

Status

approved