id:A116775 - OEIS Search Results

Search: id:A116775

Displaying 1-1 of 1 results found.

page 1

Number of permutations of length n which avoid the patterns 1234, 2341, 4132.

+0
1

1, 2, 6, 21, 72, 221, 605, 1517, 3574, 8065, 17671, 37953, 80424, 168885, 352481, 732581, 1518074, 3139033, 6480187, 13360153, 27514476, 56610861, 116377941, 239059421, 490715582, 1006612721, 2063574895, 4227833137, 8657015344 (list; graph; listen)

	OFFSET	`1,2`
	LINKS	`Lara Pudwell, Systematic Studies in Pattern Avoidance, 2005.`
	FORMULA	`G.f.: A(x) = {(4x^7-5x^6-11x^5+13x^4-19x^3+16x^2-6x+1)x}/{(2x-1)^2(x-1)^4}`
	CROSSREFS	`Sequence in context: A116801 A116750 A116791 this_sequence A116786 A116748 A116812` `Adjacent sequences: A116772 A116773 A116774 this_sequence A116776 A116777 A116778`
	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