A177627 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, up, up, down, down

1, 20, 1665, 356520, 155809035, 121055807700, 152393963368875, 290740199232531840

Offset

1,2

Links

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

Crossrefs

Sequence in context: A094035 A177614 A177622 * A177620 A177632 A177631

Adjacent sequences: A177624 A177625 A177626 * A177628 A177629 A177630

Keyword

nonn

Author

R. H. Hardin May 10 2010

Status

approved