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 A024272 #11 Apr 12 2017 23:16:19
%S A024272 0,1,6,71,1596,58141,3109986,229395011,22312837176,2767173538681,
%T A024272 426167405495166,79796244279937151,17851790220732115956,
%U A024272 4702787739658825158421,1440911869083478804851546,508062238427253843822090491,204262590490127231070131373936,92884219961086104169154295141361
%N A024272 E.g.f. tan(x)*sinh(x)/2 (even powers only).
%H A024272 G. C. Greubel, <a href="/A024272/b024272.txt">Table of n, a(n) for n = 0..240</a>
%t A024272 With[{nn = 50}, Take[CoefficientList[Series[Tan[x]*Sinh[x]/2, {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* _G. C. Greubel_, Apr 12 2017 *)
%o A024272 (PARI) x='x+O('x^66); v=Vec(serlaplace(tan(x)*sinh(x)/2)); concat([0],vector(#v\2,n,v[2*n-1])) \\ _Joerg Arndt_, Apr 26 2013
%Y A024272 A009747.
%K A024272 nonn
%O A024272 0,3
%A A024272 _R. H. Hardin_
%E A024272 Extended and signs tested 03/97.