id:A116715 - OEIS Search Results

Search: id:A116715

Displaying 1-1 of 1 results found.

page 1

Number of permutations of length n which avoid the patterns 312, 2341, 4321.

+0
1

1, 2, 5, 12, 25, 54, 120, 265, 580, 1272, 2796, 6143, 13488, 29619, 65053, 142873, 313771, 689095, 1513390, 3323699, 7299465, 16031000, 35207128, 77321545, 169812767, 372941033, 819049274, 1798787604, 3950478790, 8676000808 (list; graph; listen)

	OFFSET	`1,2`
	LINKS	`Lara Pudwell, Systematic Studies in Pattern Avoidance, 2005.`
	FORMULA	`G.f.: A(x) = -{x(x+1)(x^3+2x^2+1)}/{3x^4+x^5+2x^3+x^2+x-1}`
	CROSSREFS	`Sequence in context: A101836 A122439 A063807 this_sequence A117177 A132977 A027927` `Adjacent sequences: A116712 A116713 A116714 this_sequence A116716 A116717 A116718`
	KEYWORD	`nonn,easy`
	AUTHOR	`Lara Pudwell (Lara.Pudwell(AT)valpo.edu), Feb 26 2006`

page 1

Search completed in 0.002 seconds

Last modified December 11 12:57 EST 2009. Contains 170656 sequences.

AT&T Labs Research