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A116784
Number of permutations of length n which avoid the patterns 2314, 3241, 4312.
0
1, 2, 6, 21, 73, 244, 782, 2415, 7232, 21122, 60455, 170228, 473014, 1300271, 3543000, 9584730, 25776439, 68985676, 183892142, 488588991, 1294654352, 3422964722, 9033615431, 23805283556, 62654864998, 164741271119
OFFSET
1,2
LINKS
FORMULA
G.f.: A(x) = -{(3x^6+4x^5-27x^4+40x^3-26x^2+8x-1)x}/{(2x-1)^3(x-1)(x^2-3x+1)}
CROSSREFS
Sequence in context: A116744 A165521 A294696 * A226431 A116802 A294697
KEYWORD
nonn,easy
AUTHOR
Lara Pudwell, Feb 26 2006
STATUS
approved