A177632 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, up, down, up, down, down

1, 20, 1668, 359280, 158479620, 124510818960, 158686566550368, 306744815112615960

Offset

1,2

Links

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

Crossrefs

Sequence in context: A177622 A177627 A177620 * A177631 A177292 A266737

Adjacent sequences: A177629 A177630 A177631 * A177633 A177634 A177635

Keyword

nonn

Author

R. H. Hardin May 10 2010

Status

approved