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 A196758 #11 Feb 11 2025 13:51:00
%S A196758 5,4,9,5,3,9,3,9,9,3,5,5,1,5,3,4,1,1,5,2,1,9,3,8,9,8,7,3,2,5,3,8,3,9,
%T A196758 3,8,0,9,0,0,3,3,7,2,8,1,1,5,2,8,5,6,2,7,9,9,1,4,1,4,4,8,6,9,2,6,4,3,
%U A196758 3,4,8,0,3,1,1,8,0,1,2,5,1,7,1,0,9,1,7,7,2,2,1,6,8,3,7,7,9,3,0
%N A196758 Decimal expansion of the number c for which the curve y=1/x is tangent to the curve y=c*sin(x), and 0 < x < 2*Pi.
%e A196758 c=0.5495393993551534115219389873253839380900...
%t A196758 Plot[{1/x, .55*Sin[x]}, {x, 0, Pi}]
%t A196758 xt = x /. FindRoot[x + Tan[x] == 0, {x, 1.5, 2.5}, WorkingPrecision -> 100]
%t A196758 RealDigits[xt] (* A196504 *)
%t A196758 c = N[1/(xt*Sin[xt]), 100]
%t A196758 RealDigits[c] (* A196758 *)
%t A196758 slope = -1/xt^2
%t A196758 RealDigits[slope] (* A196759 *)
%o A196758 (PARI) t=solve(x=2,3, sin(x)-x/sqrt(1+x^2)); 1/t/sin(t) \\ _Charles R Greathouse IV_, Feb 11 2025
%Y A196758 Cf. A196624.
%K A196758 nonn,cons
%O A196758 0,1
%A A196758 _Clark Kimberling_, Oct 06 2011