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 A086725 #8 May 21 2021 15:48:36
%S A086725 1,2,7,9,9,1,4,1,3,2,4,7,1,1,2,1,2,0,6,6,1,5,4,2,9,9,4,9,3,4,0,9,2,2,
%T A086725 8,9,1,5,5,3,4,6,5,6,9,2,9,2,0,5,8,5,5,6,7,8,5,0,7,1,6,0,1,8,1,3,7,2,
%U A086725 3,3,5,8,4,4,4,5,9,4,1,5,4,3,4,4,3,8,1,0,3,5,0,1,8,3,4,0,9,1,3
%N A086725 Decimal expansion of 1/(g(1)-g(2)+g(4)-g(5)), where g(k) = Sum_{m>=0} 1/(6*m+k)^2.
%D A086725 L. Fejes Toth, Lagerungen in der Ebene, auf der Kugel und im Raum, 2nd. ed., Springer-Verlag, Berlin, Heidelberg 1972; see p. 213.
%e A086725 1.2799141324711212...
%t A086725 g[k_] := PolyGamma[1, k/6]/36; RealDigits[ 1/(g[1] - g[2] + g[4] - g[5]), 10, 99] // First (* _Jean-François Alcover_, Feb 13 2013 *)
%Y A086725 Cf. A086722-A086731.
%K A086725 nonn,cons
%O A086725 1,2
%A A086725 _N. J. A. Sloane_, Jul 31 2003