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A050390
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Exponential reversion of divisor function A000005.
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2
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1, -2, 10, -83, 968, -14550, 267657, -5823342, 146255131, -4164222891, 132539992770, -4663220787205, 179712285498419, -7528614819216452, 340644924343427080, -16555539553909999044, 860131362806819785898
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OFFSET
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1,2
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LINKS
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FORMULA
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E.g.f. A(x) satisfies: A(x) = x - Sum_{k>=2} d(k) * A(x)^k / k!. - Ilya Gutkovskiy, Apr 22 2020
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PROG
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(PARI) seq(n)= Vec(serlaplace(serreverse(sum(k=1, n, numdiv(k)*x^k/k!) + O(x*x^n)))); \\ Michel Marcus, Apr 21 2020
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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