The On-Line Encyclopedia of Integer Sequences (OEIS)

The OEIS is supported by the many generous donors to the OEIS Foundation.

A217819 revision #4

A217819

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

0

1, 5, 56, 1004, 24336, 727807

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..6.

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: A357392 A217817 A217818 * * A132618 A371314

Adjacent sequences: A217816 A217817 A217818 * A217820 A217821 A217822

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Oct 13 2012

STATUS

approved