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 A196610 #9 Apr 10 2021 08:05:04
%S A196610 1,7,8,2,2,2,5,1,4,0,2,0,3,1,3,3,3,1,2,4,0,7,5,5,1,0,3,2,6,6,6,1,6,0,
%T A196610 0,1,9,5,1,3,4,4,2,6,3,6,9,4,4,5,2,3,3,4,5,7,3,0,3,9,3,2,2,0,3,9,2,9,
%U A196610 1,5,6,2,8,3,8,7,9,3,1,2,8,0,2,8,4,6,5,8,4,5,1,5,5,2,5,7,0,6,7,9
%N A196610 Decimal expansion of the number c for which the curve y = c*cos(x) is tangent to the curve y = 1/x, and 0 < x < 2*Pi.
%e A196610 c=1.7822251402031333124075510326661600195134426369...
%t A196610 Plot[{1/x, (1.78222) Cos[x]}, {x, .7, 1}]
%t A196610 xt = x /. FindRoot[x == Cot[x], {x, .8, 1}, WorkingPrecision -> 100]
%t A196610 c = N[Csc[xt]/xt^2, 100]
%t A196610 RealDigits[c] (* A196610 *)
%t A196610 slope = -c*Sin[xt]
%t A196610 RealDigits[slope] (* A196611 *)
%Y A196610 Cf. A196603, A196611.
%K A196610 nonn,cons
%O A196610 1,2
%A A196610 _Clark Kimberling_, Oct 04 2011