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 A086232 #36 Feb 16 2025 08:32:50
%S A086232 1,9,3,2,0,1,6,7,3,2,2,4,9,8,3,9,3,7,3,4,1,8,7,0,9,7,3,3,2,9,3,6,9,1,
%T A086232 6,0,5,7,5,8,7,3,3,8,6,4,5,0,1,3,9,4,9,5,8,3,5,0,2,6,1,8,5,7,0,9,6,3,
%U A086232 2,2,9,2,4,9,5,8,1,0,8,4,6,0,2,9,4,4,3
%N A086232 Decimal expansion of probability that a random walk on a 4-d lattice returns to the origin.
%D A086232 Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 5.9, p. 323.
%H A086232 Marc Mezzarobba, <a href="/A086232/b086232.txt">Table of n, a(n) for n = 0..9999</a>
%H A086232 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PolyasRandomWalkConstants.html">Pólya's Random Walk Constants</a>.
%F A086232 Equals 1 - 1/A242812. - _Amiram Eldar_, Aug 28 2020
%e A086232 0.19320167322498393734187097332936916057587338645...
%t A086232 First[RealDigits[1 - 1/NIntegrate[BesselI[0, t/4]^4 * Exp[ -t], {t, 0, Infinity}, PrecisionGoal->50, WorkingPrecision->350]]] (* _Ryan Propper_, Jul 12 2005 *)
%Y A086232 Cf. A086230, A086233, A086234, A086235, A086236, A242812.
%K A086232 nonn,cons
%O A086232 0,2
%A A086232 _Eric W. Weisstein_, Jul 12 2003
%E A086232 More terms from _Ryan Propper_, Jul 12 2005
%E A086232 a(51) corrected and more terms using the data at A242812 added by _Amiram Eldar_, Aug 28 2020