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A360696
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Expansion of Sum_{k>=0} (x * (1 + k^k * x))^k.
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2
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1, 1, 2, 9, 98, 3212, 428525, 165045051, 342128248388, 2522279110319003, 90930729844450829580, 17690430223837969605522024, 13516362920784209950583739768297, 79459280482613898608830749440741093093
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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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a(n) = Sum_{k=0..floor(n/2)} (n-k)^(k*(n-k)) * binomial(n-k,k).
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PROG
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(PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=0, N, (x*(1+k^k*x))^k))
(PARI) a(n) = sum(k=0, n\2, (n-k)^(k*(n-k))*binomial(n-k, 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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