%I #7 Aug 09 2021 14:03:36
%S 5,1,1,4,1,8,2,1,8,7,8,5,5,8,1,5,8,7,4,9,1,9,7,7,5,5,4,8,9,2,6,8,0,0,
%T 7,7,3,5,0,5,6,3,6,1,9,9,8,1,4,4,3,8,7,6,0,0,4,6,6,2,1,8,7,5,9,2,6,8,
%U 6,5,7,6,6,0,3,4,2,7,2,0,0,9,7,7,5,6,4,3,8,5,9,1,9,9,5,0,9,7,9,6,7
%N Decimal expansion of the least x>0 satisfying 2*sec(x)=x.
%e x=5.11418218785581587491977554892680077350563...
%t Plot[{1/x, 2/x, 3/x, 4/x, Cos[x]}, {x, 0, 2 Pi}]
%t t = x /. FindRoot[1/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t RealDigits[t] (* A133868 *)
%t t = x /. FindRoot[2/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t RealDigits[t] (* A196612 *)
%t t = x /. FindRoot[3/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t RealDigits[t] (* A196613 *)
%t t = x /. FindRoot[4/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t RealDigits[t] (* A196614 *)
%t t = x /. FindRoot[5/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t RealDigits[t] (* A196615 *)
%t t = x /. FindRoot[6/x == Cos[x], {x, 4, 7}, WorkingPrecision -> 100]
%t RealDigits[t] (* A196616 *)
%Y Cf. A196604.
%K nonn,cons
%O 1,1
%A _Clark Kimberling_, Oct 04 2011
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