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%I #7 Aug 09 2021 14:03:53
%S 5,3,1,2,4,6,9,7,1,1,6,5,6,5,6,7,6,9,7,3,6,6,1,5,7,9,9,8,2,5,4,4,0,3,
%T 1,8,1,1,9,1,6,9,4,1,2,2,9,2,0,7,8,3,5,5,2,4,1,2,5,6,2,2,8,3,8,4,9,0,
%U 6,5,4,7,0,5,4,7,0,2,9,2,3,6,4,4,2,8,8,2,9,8,4,8,7,2,6,5,3,2,5,2,9
%N Decimal expansion of the least x>0 satisfying 3*sec(x)=x.
%e x=5.31246971165656769736615799825440318119169412292...
%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