A217814 Number of alternating permutations on 2n+1 letters that avoid a certain pattern of length 5 (see Lewis, 2012, Appendix, for precise definition).

1, 2, 16, 243, 5330, 148575, 4909608, 184302261, 7641026926

Offset

0,2

Links

Table of n, a(n) for n=0..8.

J. B. Lewis, Pattern Avoidance for Alternating Permutations and Reading Words of Tableaux, Ph. D. Dissertation, Department of Mathematics, MIT, 2012.

Crossrefs

Cf. A181197, A217799-A217830.

Sequence in context: A207176 A217812 A217813 * A217815 A192325 A009233

Adjacent sequences: A217811 A217812 A217813 * A217815 A217816 A217817

Keyword

nonn,more

Author

N. J. A. Sloane, Oct 13 2012

Extensions

a(6)-a(8) from Lars Blomberg, Feb 22 2018

Status

approved