id:A116735 - OEIS Search Results

Search: id:A116735

Displaying 1-1 of 1 results found.

page 1

Number of permutations of length n which avoid the patterns 231, 1234, 4312; or avoid the patterns 312, 1234, 1432, etc.

+0
1

1, 2, 5, 12, 23, 38, 57, 80, 107, 138, 173, 212, 255, 302, 353, 408, 467, 530, 597, 668, 743, 822, 905, 992, 1083, 1178, 1277, 1380, 1487, 1598 (list; graph; listen)

	OFFSET	`1,2`
	LINKS	`Lara Pudwell, Systematic Studies in Pattern Avoidance, 2005.`
	FORMULA	`G.f.: A(x) = -{(2x^3+2x^2-x+1)x}/{(x-1)^3}` `For n >= 2, a(n) = 2n^2 - 7n + 8. - Franklin T. Adams-Watters, Sep 16 2006` `a(n)=A096376(n-2), n>1. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 10 2008]`
	CROSSREFS	`Sequence in context: A116711 A109653 A115520 this_sequence A096376 A112287 A127787` `Adjacent sequences: A116732 A116733 A116734 this_sequence A116736 A116737 A116738`
	KEYWORD	`nonn,easy`
	AUTHOR	`Lara Pudwell (Lara.Pudwell(AT)valpo.edu), Feb 26 2006`

page 1

Search completed in 0.002 seconds

Last modified November 18 20:14 EST 2008. Contains 147244 sequences.

AT&T Labs Research