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A052862
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Expansion of e.g.f. log(-1/(-2+exp(x)))*x.
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7
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0, 0, 2, 6, 24, 130, 900, 7574, 74928, 851274, 10916700, 155919742, 2453941512, 42188446898, 786563892660, 15805750451430, 340522975054176, 7829628493247002, 191363568551328780, 4954089147107164238
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OFFSET
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0,3
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COMMENTS
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A simple grammar.
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LINKS
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FORMULA
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MAPLE
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spec := [S, {B=Cycle(C), C=Set(Z, 1 <= card), S=Prod(Z, B)}, labeled]: seq(combstruct[count](spec, size=n), n=0..20);
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MATHEMATICA
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Fubini[n_, r_] := Sum[k!*Sum[(-1)^(i+k+r)*((i+r)^(n-r)/(i!*(k-i-r)!)), {i, 0, k-r}], {k, r, n}];
Fubini[0, 1] = 1;
a[n_] := If[n == 2, 2, 2 n * Fubini[n-2, 1]];
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PROG
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(PARI) my(x='x+O('x^25)); concat([0, 0], Vec(serlaplace(log(-1/(-2+exp(x)))*x))) \\ Joerg Arndt, Oct 11 2022
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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encyclopedia(AT)pommard.inria.fr, Jan 25 2000
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STATUS
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approved
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