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A366751
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Expansion of e.g.f. -log(1 - x^3 * (exp(x) - 1)).
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1
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0, 0, 0, 0, 24, 60, 120, 210, 20496, 181944, 1059120, 4990590, 180292200, 3191349876, 36598884504, 327837512730, 7732754793120, 194896185648240, 3574721299186656, 51311061420097014, 1105883184455171640, 32127696556638165420, 812811279492629700360
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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_{k=1..floor(n/4)} (k-1)! * Stirling2(n-3*k,k)/(n-3*k)!.
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PROG
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(PARI) a(n) = n!*sum(k=1, n\4, (k-1)!*stirling(n-3*k, k, 2)/(n-3*k)!);
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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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