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 A197683 #11 Oct 01 2022 00:46:26
%S A197683 2,1,5,6,7,4,3,5,9,5,7,5,3,9,6,7,5,7,2,1,3,3,9,6,9,1,8,5,7,2,8,3,7,6,
%T A197683 6,6,1,9,8,9,7,6,6,1,7,7,9,8,5,8,6,5,7,6,3,0,3,1,5,4,0,7,1,0,4,9,8,8,
%U A197683 1,4,5,5,8,3,8,8,6,1,5,5,3,0,3,6,6,1,0,3,5,3,7,0,1,0,9,2,9,7,4
%N A197683 Decimal expansion of Pi/(2+4*Pi).
%C A197683 Least x>0 such that sin(bx)=cos(cx) (and also sin(cx)=cos(bx)), where b=1 and c=2*pi; see the Mathematica program for a graph and A197682 for a discussion and guide to related sequences.
%H A197683 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>
%e A197683 x=0.215674359575396757213396918572837666...
%t A197683 b = 1; c = 2*Pi;
%t A197683 t = x /. FindRoot[Sin[b*x] == Cos[c*x], {x, .2, .3}]
%t A197683 N[Pi/(2*b + 2*c), 110]
%t A197683 RealDigits[%] (* A197683 *)
%t A197683 Simplify[Pi/(2*b + 2*c)]
%t A197683 Plot[{Sin[b*x], Cos[c*x]}, {x, 0, Pi/2}]
%t A197683 RealDigits[Pi/(2+4Pi),10,120][[1]] (* _Harvey P. Dale_, Oct 27 2016 *)
%Y A197683 Cf. A197682.
%K A197683 nonn,cons
%O A197683 0,1
%A A197683 _Clark Kimberling_, Oct 17 2011