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A201409
Decimal expansion of greatest x satisfying 3*x^2 = sec(x) and 0 < x < Pi.
3
1, 3, 9, 9, 8, 6, 4, 1, 1, 9, 4, 4, 6, 0, 6, 4, 0, 6, 7, 2, 2, 9, 6, 3, 9, 5, 0, 5, 1, 8, 3, 6, 1, 0, 3, 7, 3, 9, 4, 1, 7, 8, 5, 0, 3, 3, 6, 2, 5, 3, 2, 6, 3, 4, 4, 2, 0, 4, 1, 4, 9, 8, 8, 7, 0, 4, 9, 5, 8, 0, 2, 7, 1, 7, 3, 5, 1, 0, 6, 0, 0, 3, 3, 5, 7, 9, 7, 0, 2, 0, 5, 7, 8, 1, 6, 5, 9, 1, 9
OFFSET
1,2
COMMENTS
See A201397 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: 0.6461374540628972972901679159101125226952859...
greatest: 1.39986411944606406722963950518361037394178...
MATHEMATICA
a = 3; c = 0;
f[x_] := a*x^2 + c; g[x_] := Sec[x]
Plot[{f[x], g[x]}, {x, 0, Pi/2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, .6, .7}, WorkingPrecision -> 110]
RealDigits[r] (* A201408 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.3, 1.4}, WorkingPrecision -> 110]
RealDigits[r] (* A201409 *)
CROSSREFS
Cf. A201397.
Sequence in context: A084762 A188444 A372914 * A111120 A100401 A004166
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Dec 01 2011
STATUS
approved