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A294816
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Number of permutations of [n] avoiding {1342, 2314, 4231}.
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0
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1, 1, 2, 6, 21, 75, 267, 951, 3407, 12309, 44867, 164891, 610347, 2273020, 8508804, 31991549, 120734511, 457129176, 1735730619, 6607223257, 25207606841, 96365703918, 369070368271, 1415863217868, 5439991258764, 20930861647331, 80638367290921, 311043531047557, 1201127506963082
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OFFSET
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0,3
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LINKS
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MAPLE
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C := (1-sqrt(1-4*x))/2/x ;
(1 -7*x +18*x^2 -22*x^3 +16*x^4 -6*x^5 +x^6 -(x -5*x^2 +8*x^3 -2*x^4 -2*x^5 +x^6)*C)/((1 -2*x)*(1 -x)^2*(1 -5*x +4*x^2 -x^3)) ;
taylor(%, x=0, 40) ;
gfun[seriestolist](%) ;
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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