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%I #7 Aug 09 2021 14:04:21
%S 5,7,6,2,8,0,9,4,5,6,0,9,0,9,8,8,0,3,3,0,0,7,3,0,0,1,5,2,9,9,9,9,5,3,
%T 3,5,6,6,7,6,8,1,9,6,8,0,7,1,2,0,5,6,6,6,8,0,8,3,2,4,9,4,4,8,5,3,2,7,
%U 4,1,9,7,7,9,1,4,0,1,0,3,8,1,8,6,7,5,1,3,9,0,3,4,8,4,4,7,2,6,9,2,6,9,7,8,9
%N Decimal expansion of the least x>0 satisfying 5*sec(x)=x.
%e x=5.762809456090988033007300152999953356676...
%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 *)
%K nonn,cons
%O 1,1
%A _Clark Kimberling_, Oct 05 2011