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A367877
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Expansion of e.g.f. exp(x * (3 - 2*exp(x))).
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1
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1, 1, -3, -17, -7, 331, 1669, -2561, -82447, -411821, 1602941, 38344615, 209694121, -1133998085, -29424823819, -194721585329, 978185645537, 33795275629219, 290738927334637, -827164853506313, -53319390538573159, -621202281347942069, -249829452752930203
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OFFSET
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0,3
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LINKS
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FORMULA
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G.f.: Sum_{k>=0} (-2*x)^k / (1 - (k+3)*x)^(k+1).
a(n) = Sum_{k=0..n} (-2)^k * (k+3)^(n-k) * binomial(n,k).
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PROG
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(PARI) a(n) = sum(k=0, n, (-2)^k*(k+3)^(n-k)*binomial(n, k));
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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STATUS
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approved
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