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A283335
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Expansion of exp( Sum_{n>=1} -A062796(n)/n*x^n ) in powers of x.
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2
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1, -1, -2, -7, -54, -544, -7005, -108220, -1958263, -40629205, -951376217, -24826365255, -714568797261, -22491957589783, -768651303338761, -28344950796904518, -1121910285249842486, -47442295013058570884, -2134673855370621621400
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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.: Product_{k>=1} (1 - x^k)^(k^(k-1)).
a(n) = -(1/n)*Sum_{k=1..n} A062796(k)*a(n-k) for n > 0.
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MATHEMATICA
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A[n_] := Sum[d^d, {d, Divisors[n]}]; a[n_] := If[n==0, 1, -(1/n)*Sum[A[k]*a[n - k], {k, n}]]; Table[a[n], {n, 0, 18}] (* Indranil Ghosh, Mar 11 2017 *)
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PROG
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(PARI) a(n) = if(n==0, 1, -(1/n)*sum(k=1, n, sumdiv(k, d, d^d)*a(n - k)));
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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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