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Expansion of exp( Sum_{n>=1} -A062796(n)/n*x^n ) in powers of x.
2

%I #24 Mar 12 2017 12:29:16

%S 1,-1,-2,-7,-54,-544,-7005,-108220,-1958263,-40629205,-951376217,

%T -24826365255,-714568797261,-22491957589783,-768651303338761,

%U -28344950796904518,-1121910285249842486,-47442295013058570884,-2134673855370621621400

%N Expansion of exp( Sum_{n>=1} -A062796(n)/n*x^n ) in powers of x.

%H Seiichi Manyama, <a href="/A283335/b283335.txt">Table of n, a(n) for n = 0..387</a>

%F G.f.: Product_{k>=1} (1 - x^k)^(k^(k-1)).

%F a(n) = -(1/n)*Sum_{k=1..n} A062796(k)*a(n-k) for n > 0.

%t 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 *)

%o (PARI) a(n) = if(n==0, 1, -(1/n)*sum(k=1, n, sumdiv(k, d, d^d)*a(n - k)));

%o for(n=0, 18, print1(a(n), ", ")) \\ _Indranil Ghosh_, Mar 11 2017

%Y Cf. A023879 (exp( Sum_{n>=1} A062796(n)/n*x^n )), A062796.

%K sign

%O 0,3

%A _Seiichi Manyama_, Mar 08 2017