A177658 Number of permutations of 4 copies of 1..n avoiding adjacent step pattern up, down, down, down, down, up.

1, 1, 70, 34650, 63063000, 304028985024, 3200982922029530, 64736431797158097635

Offset

0,3

Links

Table of n, a(n) for n=0..7.

Crossrefs

Cf. A014608.

Sequence in context: A266741 A177646 A177647 * A177670 A177671 A177656

Adjacent sequences: A177655 A177656 A177657 * A177659 A177660 A177661

Keyword

nonn

Author

R. H. Hardin, May 10 2010

Status

approved