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 A265975 #11 Aug 23 2019 20:51:12
%S A265975 1,4,24,108,512,2164,9464,39004,163008,663588,2713752,10954764,
%T A265975 44328512,178160724,716821752,2874497660,11532111232,46187508676,
%U A265975 185028540696,740595436652,2964628293504,11862432443764,47467812675320,189902835709212,759756868215872
%N A265975 Expansion of Product_{k>=1} 1/(1 - 4*k*x^k).
%H A265975 Vaclav Kotesovec, <a href="/A265975/b265975.txt">Table of n, a(n) for n = 0..1000</a>
%F A265975 a(n) ~ c * 4^n, where c = Product_{m>=2} 1/(1 - m/4^(m-1)) = 2.700170514502619666262858845683166558216386190684736249639219328278569...
%p A265975 b:= proc(n, i) option remember; `if`(n=0 or i=1,
%p A265975 4^n, b(n, i-1) +i*4*b(n-i, min(n-i, i)))
%p A265975 end:
%p A265975 a:= n-> b(n$2):
%p A265975 seq(a(n), n=0..32); # _Alois P. Heinz_, Aug 23 2019
%t A265975 nmax=40; CoefficientList[Series[Product[1/(1-4*k*x^k), {k, 1, nmax}], {x, 0, nmax}], x]
%Y A265975 Cf. A006906, A265951, A265974, A265976.
%Y A265975 Cf. A246935, A246936.
%K A265975 nonn
%O A265975 0,2
%A A265975 _Vaclav Kotesovec_, Dec 19 2015