%I #6 Mar 30 2012 18:57:50
%S 1,4,0,1,2,6,9,2,0,7,5,9,9,9,5,7,9,4,2,9,2,7,1,8,7,2,4,3,7,9,0,8,3,4,
%T 1,9,1,5,3,0,8,8,2,8,6,5,4,5,3,3,6,0,2,6,0,3,7,9,1,7,8,2,5,0,7,8,6,3,
%U 1,6,4,0,0,0,4,3,1,7,1,7,3,3,3,7,3,4,8,3,3,1,2,5,9,5,7,5,7,7,9,3
%N Decimal expansion of the least x>0 satisfying 1/(1+x^2)=2*cos(x).
%e x=1.401269207599957942927187243790834191530882865453360260...
%t Plot[{1/(1 + x^2), Cos[x], 2 Cos[x], 3 Cos[x], 4 Cos[x]}, {x, 0, 2}]
%t t = x /. FindRoot[1 == (1 + x^2) Cos[x], {x, 1, 1.5}, WorkingPrecision -> 100]
%t RealDigits[t] (* A196816 *)
%t t = x /. FindRoot[1 == 2 (1 + x^2) Cos[x], {x, 1, 1.6},
%t WorkingPrecision -> 100]
%t RealDigits[t] (* A196817 *)
%t t = x /. FindRoot[1 == 3 (1 + x^2) Cos[x], {x, 1, 1.6},
%t WorkingPrecision -> 100]
%t RealDigits[t] (* A196818 *)
%t t = x /. FindRoot[1 == 4 (1 + x^2) Cos[x], {x, 1, 1.6},
%t WorkingPrecision -> 100]
%t RealDigits[t] (* A196819 *)
%t t = x /. FindRoot[1 == 5 (1 + x^2) Cos[x], {x, 1, 1.6},
%t WorkingPrecision -> 100]
%t RealDigits[t] (* A196820 *)
%t t = x /. FindRoot[1 == 6 (1 + x^2) Cos[x], {x, 1, 1.6},
%t WorkingPrecision -> 100]
%t RealDigits[t] (* A196821 *)
%Y Cf. A196914.
%K nonn,cons
%O 1,2
%A _Clark Kimberling_, Oct 06 2011
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