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A116714
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Number of permutations of length n which avoid the patterns 321, 1342, 4123.
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1
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1, 2, 5, 12, 24, 46, 87, 162, 300, 554, 1021, 1880, 3460, 6366, 11711, 21542, 39624, 72882, 134053, 246564, 453504, 834126, 1534199, 2821834, 5190164, 9546202, 17558205, 32294576, 59398988, 109251774, 200945343, 369596110, 679793232
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Lara Pudwell, Systematic Studies in Pattern Avoidance, 2005.
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FORMULA
| G.f.: A(x) = {(x^4+2x^3+x^2+1)x}/{(x-1)(x^3+x^2+x-1)}
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MAPLE
| A116714 := proc(n) coeftayl(x*(x^4+2*x^3+x^2+1)/(x-1)/(x^3+x^2+x-1), x=0, n) ; end: seq(A116714(n), n=1..50) ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 22 2008
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CROSSREFS
| Sequence in context: A116721 A192981 A116713 * A023615 A034483 A096584
Adjacent sequences: A116711 A116712 A116713 * A116715 A116716 A116717
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KEYWORD
| nonn,easy
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AUTHOR
| Lara Pudwell (Lara.Pudwell(AT)valpo.edu), Feb 26 2006
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 22 2008
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