A285287 - OEIS

%I #12 Apr 16 2017 10:27:32

%S 1,-1,1,-1,1,-6,6,-6,6,-15,30,-30,30,-43,88,-123,123,-140,250,-385,

%T 455,-476,678,-1098,1413,-1564,1913,-2918,4048,-4707,5452,-7572,10747,

%U -13265,15195,-19534,27349,-35146,41042,-50011,67596,-88897,106519,-126635,164230

%N Expansion of Product_{k>=0} 1/(1 + x^(4*k+1))^(4*k+1).

%H Seiichi Manyama, <a href="/A285287/b285287.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = (-1)^n * A285048(n).

%t nmax = 50; CoefficientList[Series[Product[1/(1 + x^(4*k-3))^(4*k-3), {k,1,nmax}], {x,0,nmax}], x] (* _Vaclav Kotesovec_, Apr 16 2017 *)

%Y Product_{k>=0} 1/(1 + x^(m*k+1))^(m*k+1): A284628 (m=2), A285286 (m=3), this sequence (m=4).

%Y Cf. A285048, A285288.

%K sign

%O 0,6

%A _Seiichi Manyama_, Apr 16 2017