A177610 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, down, up, down, down.

1, 20, 1596, 320048, 129324340, 92116698310, 105699012290844, 183051978088671332

Offset

1,2

Links

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

Crossrefs

Sequence in context: A177625 A203481 A177608 * A130040 A331563 A250018

Adjacent sequences: A177607 A177608 A177609 * A177611 A177612 A177613

Keyword

nonn

Author

R. H. Hardin, May 10 2010

Status

approved