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A201400
Decimal expansion of x satisfying x^2 + 5 = sec(x) and 0 < x < Pi.
2
1, 4, 2, 8, 2, 6, 7, 7, 6, 5, 8, 3, 8, 2, 2, 2, 6, 4, 0, 3, 3, 9, 7, 6, 6, 3, 0, 1, 3, 2, 5, 2, 7, 7, 6, 0, 6, 6, 2, 8, 1, 3, 1, 0, 7, 4, 1, 3, 2, 3, 8, 0, 7, 8, 8, 4, 1, 0, 0, 4, 1, 5, 6, 5, 2, 4, 2, 1, 0, 7, 6, 0, 2, 9, 0, 4, 3, 2, 9, 3, 4, 0, 3, 3, 3, 5, 3, 6, 2, 7, 9, 5, 1, 4, 8, 7, 2, 6, 6
OFFSET
1,2
COMMENTS
See A201397 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=1.42826776583822264033976630132527760662...
MATHEMATICA
a = 1; c = 5;
f[x_] := a*x^2 + c; g[x_] := Sec[x]
Plot[{f[x], g[x]}, {x, 0, Pi}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]
RealDigits[r] (* A201400 *)
CROSSREFS
Cf. A201397.
Sequence in context: A211883 A083489 A065464 * A040015 A144926 A153016
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Dec 01 2011
STATUS
approved