A177609 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, down, up, up

1, 20, 1644, 343010, 144972862, 108488657665, 131237713050591, 240253621967060451

Offset

1,2

Links

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

Crossrefs

Sequence in context: A177621 A177628 A177626 * A094035 A177614 A177622

Adjacent sequences: A177606 A177607 A177608 * A177610 A177611 A177612

Keyword

nonn

Author

R. H. Hardin May 10 2010

Status

approved