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A111534
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Main diagonal of table A111528.
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7
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1, 1, 4, 33, 416, 7045, 149472, 3804353, 112784896, 3812791581, 144643185600, 6081135558817, 280510445260800, 14080668974435141, 763890295406672896, 44529851124925034625, 2775373003913373810688, 184147301185264051623181
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OFFSET
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0,3
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COMMENTS
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For n>0, a(n) is divisible by n: a(n)/n = A111535(n).
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LINKS
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FORMULA
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a(n) = [x^n] Log( Sum_{m=0..n} (n-1+m)!/(n-1)!*x^m ).
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MATHEMATICA
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T[n_, k_] := T[n, k] = Which[n<0 || k<0, 0, k==0 || k==1, 1, n==0, k!, True, (T[n-1, k+1]-T[n-1, k])/n - Sum[T[n, j] T[n-1, k-j], {j, 1, k-1}]];
a[n_] := T[n, n];
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PROG
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(PARI) {a(n)=if(n<0, 0, if(n==0, 1, polcoeff(log(sum(m=0, n, (n-1+m)!/(n-1)!*x^m)), n)))}
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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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