This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A278558 #20 Nov 28 2016 06:01:40
%S A278558 1,31,527,6448,63240,526443,3852742,25380847,153068700,855816380,
%T A278558 4479330091,22117432019,103672066076,463698703204,1987628351600,
%U A278558 8195086588810,32603090921532,125497791966435,468512597653134,1699911932127300,6005651320362628,20693956328627358
%N A278558 Expansion of Product_{n>=1} (1 - x^(5*n))^30/(1 - x^n)^31 in powers of x.
%C A278558 In general, if m>0 and g.f. = Product_{k>=1} (1 - x^(5*k))^m/(1 - x^k)^(m+1) then a(n) ~ sqrt(4*m+5) * exp(Pi*sqrt(2*(4*m+5)*n/15)) / (4*sqrt(3)*5^((m+1)/2)*n). - _Vaclav Kotesovec_, Nov 28 2016
%H A278558 Seiichi Manyama, <a href="/A278558/b278558.txt">Table of n, a(n) for n = 0..1000</a>
%F A278558 G.f.: Product_{n>=1} (1 - x^(5*n))^30/(1 - x^n)^31.
%F A278558 A278559(n) = 5^2*63*A160460(n) + 5^5*52*A278555(n-1) + 5^7*63*A278556(n-2) + 5^10*6*A278557(n-3) + 5^12*a(n-4) for n >= 4.
%F A278558 a(n) ~ exp(Pi*5*sqrt(2*n/3)) / (24414062500*sqrt(3)*n). - _Vaclav Kotesovec_, Nov 28 2016
%t A278558 nmax = 50; CoefficientList[Series[Product[(1 - x^(5*k))^30/(1 - x^k)^31, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Nov 28 2016 *)
%Y A278558 Cf. A160460, A278555, A278556, A278557, A278559.
%K A278558 nonn
%O A278558 0,2
%A A278558 _Seiichi Manyama_, Nov 23 2016