OFFSET

0,3

LINKS

Darla Kremer and Wai Chee Shiu, Finite transition matrices for permutations avoiding pairs of length four patterns, Discrete Math. 268 (2003), 171-183. MR1983276 (2004b:05006). See Table 1.

EXAMPLE

There are 22 permutations of length 4 which avoid these two patterns, so a(4)=22.

CROSSREFS

KEYWORD

nonn,more

AUTHOR

Vincent Vatter, Sep 21 2009

EXTENSIONS

The 6th term should be 381, not 3381. Sorry about that. - Vincent Vatter, Oct 01 2010

a(0)=1 prepended by Alois P. Heinz, Dec 09 2015

a(13)-a(15) from Lars Blomberg, Apr 26 2018

STATUS

approved