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 A032309 #15 Sep 20 2018 17:44:23
%S A032309 1,2,4,14,20,50,112,190,328,666,1340,2038,3740,5954,10792,19542,30048,
%T A032309 48290,80164,124694,204484,347610,515184,810750,1240296,1932722,
%U A032309 2887820,4557838,7126652,10463330,15768168,23499934
%N A032309 "EFK" (unordered, size, unlabeled) transform of 2,4,6,8,...
%H A032309 Vaclav Kotesovec, <a href="/A032309/b032309.txt">Table of n, a(n) for n = 0..5000</a>
%H A032309 C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>
%F A032309 G.f.: Product_{k >= 1} (1 + 2*k*x^k).
%t A032309 nmax=40; CoefficientList[Series[Product[(1+2*k*x^k), {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Dec 19 2015 *)
%o A032309 (PARI) seq(n)={Vec(prod(k=1, n, 1 + 2*k*x^k + O(x*x^n)))} \\ _Andrew Howroyd_, Sep 20 2018
%Y A032309 Cf. A022629, A032302, A265951, A265955.
%K A032309 nonn
%O A032309 0,2
%A A032309 _Christian G. Bower_
%E A032309 a(0)=1 prepended by _Andrew Howroyd_, Sep 20 2018