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%I #14 Mar 01 2024 19:16:33
%S 1,-2,-6,-4,22,72,84,-32,-474,-1310,-1728,60,6420,18712,31080,24992,
%T -34074,-186468,-430138,-650612,-496296,687120,3599652,8413968,
%U 13374148,12772246,-3910080,-50592280,-136089520,-244815336,-309079848,-176916784,391358838
%N Expansion of Product_{k>=1} ((1 - k*x^k) / (1 + k*x^k))^k.
%H Robert Israel, <a href="/A305745/b305745.txt">Table of n, a(n) for n = 0..6234</a>
%F Convolution of A266964 and A266971.
%F Convolution inverse of A266942.
%p N:= 50: # for a(0) .. a(N)
%p f:= mul(((1-k*x^k)/(1+k*x^k))^k,k=1..N):
%p S:= series(f,x,N+1):
%p seq(coeff(S,x,i),i=0..N); # _Robert Israel_, Mar 01 2024
%o (PARI) N=99; x='x+O('x^N); Vec(prod(k=1, N, ((1-k*x^k)/(1+k*x^k))^k))
%Y Cf. A266942, A266964, A266971, A292317.
%K sign
%O 0,2
%A _Seiichi Manyama_, Jun 09 2018