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 A241532 #13 Mar 13 2015 10:54:38
%S A241532 6,3,0,4,7,3,5,0,3,3,7,4,3,8,6,7,9,6,1,2,2,0,4,0,1,9,2,7,1,0,8,7,8,9,
%T A241532 0,4,3,5,4,5,8,7,0,7,8,7,1,2,7,3,2,3,4,1,5,7,3,8,1,7,9,8,3,7,0,8,9,7,
%U A241532 0,0,0,3,8,2,9,9,5,8,1,9,1,1,0,1,8,9,9,5,4,1,6,5,7,8,1,7,1,9,0,9
%N A241532 Decimal expansion of 2*e^(-2*gamma), gamma being the Euler constant.
%C A241532 See Table 1, last row, first column, of the Bailey, Borwein and Crandall link. - _Wolfdieter Lang_, Apr 25 2014
%H A241532 D.H. Bailey, J.M. Borwein, R.E. Crandall, <a href="http://crd-legacy.lbl.gov/~dhbailey/dhbpapers/ising.pdf">Integrals of the Ising class</a>
%F A241532 Limit_{n -> infinity} (2^n/n!)*integral_{0..infinity} p*BesselK(0,p)^n dp. - after Bailey & Borwein.
%F A241532 Equals 2*A080130^2.
%e A241532 0.6304735033743867961220401927108789...
%t A241532 RealDigits[2*E^(-2*EulerGamma), 10, 100] // First
%Y A241532 Cf. A073004, A080130.
%K A241532 nonn,cons
%O A241532 0,1
%A A241532 _Jean-François Alcover_, Apr 25 2014