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 A012465 #8 Nov 28 2016 18:55:40
%S A012465 1,0,12,-480,31248,-3160320,462297792,-92467554816,24237361774848,
%T A012465 -8058187934539776,3312017870282345472,-1648428171351870627840,
%U A012465 976764310209146448384000,-679332936418413117235200000
%N A012465 cosh(arctan(x)*arctan(x))=1+12/4!*x^4-480/6!*x^6+31248/8!*x^8...
%t A012465 nn = 20; Table[(CoefficientList[Series[Cosh[ArcTan[x]^2], {x, 0, 2*nn}], x] * Range[0, 2*nn]!)[[n]], {n, 1, 2*nn+1, 2}] (* _Vaclav Kotesovec_, Feb 08 2015 *)
%K A012465 sign
%O A012465 0,3
%A A012465 Patrick Demichel (patrick.demichel(AT)hp.com)