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%I #14 Mar 04 2017 11:13:18
%S 1,-5,2,15,12,-36,-92,-17,167,358,283,-293,-1321,-2012,-1101,2299,
%T 7296,10505,6901,-7705,-31240,-52490,-51336,-6032,91521,217064,303776,
%U 250595,-36282,-575622,-1234465,-1684515,-1448538,-66980,2610835,6087681,8990575
%N Expansion of exp( Sum_{n>=1} -sigma_2(2*n)*x^n/n ) in powers of x.
%H Seiichi Manyama, <a href="/A283242/b283242.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = -(1/n)*Sum_{k=1..n} sigma_2(2*k)*a(n-k). - _Seiichi Manyama_, Mar 04 2017
%Y Cf. A283224 (exp( Sum_{n>=1} sigma_2(2*n)*x^n/n )).
%Y Cf. exp( Sum_{n>=1} -sigma_k(2*n)*x^n/n ): A115110 (k=1), this sequence (k=2).
%Y Cf. exp( Sum_{n>=1} -sigma_2(m*n)*x^n/n ): A073592 (m=1), this sequence (m=2), A283243 (m=3).
%K sign
%O 0,2
%A _Seiichi Manyama_, Mar 03 2017