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 A196609 #5 Mar 30 2012 18:57:50
%S A196609 1,3,8,0,6,0,8,5,2,5,6,4,7,7,5,6,7,2,9,1,2,8,1,9,8,3,6,9,2,9,5,0,5,6,
%T A196609 6,1,5,4,5,8,8,3,6,0,2,5,5,6,2,8,7,4,4,9,8,3,4,3,0,6,7,8,1,2,9,0,8,8,
%U A196609 1,1,9,4,1,2,0,9,1,1,5,1,7,6,1,3,1,8,3,7,9,3,8,5,4,0,5,2,7,5,4,8
%N A196609 Decimal expansion of the least x>0 satisfying 1=x*cos(4*x).
%e A196609 x=1.3806085256477567291281983692950566154588360255628744...
%t A196609 Plot[{1/x, Cos[x], Cos[2 x], Cos[3 x], Cos[4 x]}, {x, 0, 2 Pi}]
%t A196609 t = x /. FindRoot[1/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t A196609 RealDigits[t] (* A133868 *)
%t A196609 t = x /. FindRoot[1/x == Cos[2 x], {x, 2, 3}, WorkingPrecision -> 100]
%t A196609 RealDigits[t] (* A196608 *)
%t A196609 t = x /. FindRoot[1/x == Cos[3 x], {x, 1, 2}, WorkingPrecision -> 100]
%t A196609 RealDigits[t] (* A196602 *)
%t A196609 t = x /. FindRoot[1/x == Cos[4 x], {x, .9, 1.4}, WorkingPrecision -> 100]
%t A196609 RealDigits[t] (* A196609 *)
%t A196609 t = x /. FindRoot[1/x == Cos[5 x], {x, .9, 1.2}, WorkingPrecision -> 100]
%t A196609 RealDigits[t] (* A196626 *)
%K A196609 nonn,cons
%O A196609 1,2
%A A196609 _Clark Kimberling_, Oct 05 2011