A201402 - OEIS

%I #8 Apr 10 2021 16:57:47

%S 1,4,6,1,1,0,5,3,6,4,6,3,0,1,6,7,7,8,2,2,7,7,7,8,0,7,0,2,7,3,7,6,2,2,

%T 0,7,2,6,5,2,7,6,0,9,7,5,5,9,9,9,4,2,4,9,5,8,9,4,8,7,0,4,1,8,9,8,4,8,

%U 3,9,0,9,6,5,4,3,1,6,8,7,6,7,2,8,6,8,9,6,4,2,3,0,3,7,4,4,9,6,3

%N Decimal expansion of x satisfying x^2 + 7 = sec(x) and 0 < x < Pi.

%C See A201397 for a guide to related sequences. The Mathematica program includes a graph.

%e x=1.461105364630167782277780702737622072652...

%t a = 1; c = 7;

%t f[x_] := a*x^2 + c; g[x_] := Sec[x]

%t Plot[{f[x], g[x]}, {x, 0, Pi}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]

%t RealDigits[r]    (* A201402 *)

%Y Cf. A201397.

%K nonn,cons

%O 1,2

%A _Clark Kimberling_, Dec 01 2011