A177564 Number of permutations of 2 copies of 1..n avoiding adjacent step pattern up, up, up, up.

1, 1, 6, 90, 2520, 112681, 7368841, 663399996, 78683697960, 11891546908080, 2230852444731961, 508662924427157281, 138544315556694333336, 44427011758118629606980, 16567455622575976083141540, 7109119064485787682672633841, 3478010197625548606811131876321

Offset

0,3

Links

Table of n, a(n) for n=0..16.

Mingjia Yang and Doron Zeilberger, Increasing Consecutive Patterns in Words, arXiv:1805.06077 [math.CO], 2018.

Mingjia Yang, An experimental walk in patterns, partitions, and words, Ph. D. Dissertation, Rutgers University (2020).

Crossrefs

Cf. A177558, A177574, A177594.

Sequence in context: A132467 A177284 A266735 * A177565 A177576 A177588

Adjacent sequences: A177561 A177562 A177563 * A177565 A177566 A177567

Keyword

nonn

Author

R. H. Hardin, May 10 2010

Extensions

a(12)-a(14) from Alois P. Heinz, Nov 01 2013

a(0), a(15)-a(16) from Alois P. Heinz, Aug 08 2018

Status

approved