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 A138285 #2 Mar 30 2012 17:22:47
%S A138285 1,8,0,9,3,6,1,3,4,1,2,9,5,7,0,3,3,1,9,0,1,6,2,7,6,1,0,0,1,9,4,0,1,1,
%T A138285 3,2,5,6,0,0,0,7,6,2,2,4,4,0,5,3,8,5,5,8,8,2,4,4,6,6,5,4,6,2,4,8,3,7,
%U A138285 9,0,4,3,8,3,7,3,5,7,3,2,5,4,2,8,6,7,4,8,6,5,8,9,1,4,1,1,1,7,0,3,0,8,2,4,4
%N A138285 Decimal expansion of the imaginary part of z0, the smallest second-quadrant solution of z = Cos(z).
%C A138285 z0 is a repelling fixed point of Cos(z). The only fixed point on the real axis is 0.73908... (A003957), which is an attracting fixed point.
%e A138285 1.809361341295703319016276...
%t A138285 z0 = FindRoot[{Re[Cos[x+I*y]]==x, Im[Cos[x+I*y]]==y}, {{x,-2},{y,2}}, WorkingPrecision->150]; RealDigits[z0[[2,2]]]
%Y A138285 Cf. A138284 (real part).
%K A138285 cons,nonn
%O A138285 1,2
%A A138285 _T. D. Noe_, Mar 12 2008