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A116753
Number of permutations of length n which avoid the patterns 2134, 3241, 4312.
0
1, 2, 6, 21, 73, 236, 705, 1970, 5224, 13307, 32866, 79251, 187523, 437030, 1005935, 2291536, 5174458, 11596189, 25816552, 57141641, 125822061, 275766912, 601872301, 1308610526, 2835334908, 6123666671, 13186871710, 28319917295
OFFSET
1,2
LINKS
FORMULA
G.f.: A(x) = -{x(8x^7-41x^6+84x^5-103x^4+79x^3-36x^2+9x-1)}/{(2x-1)^3(x-1)^5}
CROSSREFS
Sequence in context: A116739 A116770 A294796 * A294762 A294797 A294763
KEYWORD
nonn,easy
AUTHOR
Lara Pudwell, Feb 26 2006
STATUS
approved