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 A085386 #7 Mar 17 2013 10:48:54
%S A085386 1,0,1,3,4,10,46,126,316,1296,5356,17380,63856,296088,1264264,4940040,
%T A085386 22302736,110455936,507711376,2313783216,11798364736,61878663840,
%U A085386 309240315616,1587272962528,8792390355904,48793502304000
%N A085386 E.g.f. cosh(x+x^2/2).
%C A085386 a(n) is the number of involutions with an even number of cycles. - _Geoffrey Critzer_, Mar 17 2013
%F A085386 a(n)=(A000085(n)+A001464(n))/2
%t A085386 nn=25;Range[0,nn]!CoefficientList[Series[Cosh[x+x^2/2],{x,0,nn}],x] (* _Geoffrey Critzer_, Mar 17 2013 *)
%Y A085386 Cf. A085387.
%K A085386 easy,nonn
%O A085386 0,4
%A A085386 _Paul Barry_, Jun 27 2003