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 A335931 #4 Jul 04 2020 01:45:09
%S A335931 1,2,1,6,0,0,6,7,2,3,4,2,4,9,7,9,7,8,0,3,1,2,5,9,2,7,2,3,2,8,0,8,5,4,
%T A335931 7,0,5,6,4,0,3,0,7,6,3,2,1,6,4,3,8,3,4,6,0,0,5,8,3,6,3,1,6,9,2,3,5,8,
%U A335931 9,3,3,3,9,1,8,7,6,5,4,5,0,7,9,6,7,4
%N A335931 Decimal expansion of (1/Pi)*arclength on y = sin(x) from (0,0) to (Pi,0).
%e A335931 (arclength)/(segment length) = 1.21600672342497978031259272328085470564030...
%t A335931 r = NIntegrate[Sqrt[1 + Cos[t]^2]/Pi, {t, 0, Pi}, WorkingPrecision -> 200]
%t A335931 RealDigits[r][[1]]
%Y A335931 Cf. A335928, A335929, A335930, A335932.
%K A335931 nonn,cons
%O A335931 1,2
%A A335931 _Clark Kimberling_, Jul 03 2020