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 A197690 #11 Oct 01 2022 00:48:30
%S A197690 3,0,5,5,0,7,7,3,5,1,7,5,8,2,8,6,4,4,6,9,0,2,9,7,6,9,3,9,7,6,9,8,4,4,
%T A197690 3,0,8,6,8,7,1,1,3,1,6,4,7,8,0,4,6,3,9,7,6,0,4,4,5,8,3,8,7,5,2,1,2,3,
%U A197690 2,4,1,6,9,6,8,1,5,7,9,1,9,3,2,8,6,8,5,6,9,1,7,2,8,3,3,7,1,5,2
%N A197690 Decimal expansion of Pi/(4 + 2*Pi).
%C A197690 Least x > 0 such that sin(b*x)=cos(c*x) (and also sin(c*x)=cos(b*x)), where b=2 and c=Pi; see the Mathematica program for a graph and A197682 for a discussion and guide to related sequences.
%H A197690 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%e A197690 0.30550773517582864469029769397698443086...
%t A197690 b = 2; c = Pi;
%t A197690 t = x /. FindRoot[Sin[b*x] == Cos[c*x], {x, .3, .31}]
%t A197690 N[Pi/(2*b + 2*c), 110]
%t A197690 RealDigits[%] (* A197690 *)
%t A197690 Simplify[Pi/(2*b + 2*c)]
%t A197690 Plot[{Sin[b*x], Cos[c*x]}, {x, 0, Pi/2}]
%Y A197690 Cf. A197682.
%K A197690 nonn,cons
%O A197690 0,1
%A A197690 _Clark Kimberling_, Oct 17 2011