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A371160
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Expansion of e.g.f. 1/(1 - x^3 - x^4)^x.
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3
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1, 0, 0, 0, 24, 120, 0, 2520, 60480, 544320, 3024000, 59875200, 1277337600, 16086470400, 214313299200, 4903778880000, 104439592857600, 1837718378496000, 38947773376512000, 1008640624223232000, 24160068553420800000, 570728399843137536000
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OFFSET
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0,5
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LINKS
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FORMULA
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a(n) = n! * Sum_{j=0..floor(n/3)} Sum_{k=0..j} binomial(j,n-3*j-k) * |Stirling1(j,k)|/j!.
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PROG
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(PARI) a(n) = n!*sum(j=0, n\3, sum(k=0, j, binomial(j, n-3*j-k)*abs(stirling(j, k, 1))/j!));
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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