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A201413
Decimal expansion of greatest x satisfying 5*x^2 = sec(x) and 0 < x < Pi.
3
1, 4, 7, 9, 2, 7, 1, 0, 6, 5, 2, 9, 0, 4, 1, 0, 7, 9, 3, 1, 0, 4, 2, 8, 5, 3, 4, 1, 5, 5, 3, 7, 6, 0, 2, 6, 3, 3, 4, 3, 0, 8, 8, 6, 0, 3, 8, 0, 1, 4, 0, 0, 2, 7, 0, 9, 5, 6, 1, 9, 9, 2, 7, 1, 9, 5, 9, 0, 7, 5, 2, 5, 0, 0, 9, 1, 6, 6, 2, 6, 7, 9, 0, 3, 1, 8, 7, 1, 0, 0, 1, 7, 8, 4, 7, 3, 9, 2, 1, 8, 7
OFFSET
1,2
COMMENTS
See A201397 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: 0.474127690420775415934748938569551538434...
greatest: 1.4792710652904107931042853415537602633...
MATHEMATICA
a = 5; 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, .4, .5}, WorkingPrecision -> 110]
RealDigits[r] (* A201412 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]
RealDigits[r] (* A201413 *)
CROSSREFS
Cf. A201397.
Sequence in context: A107905 A258707 A010299 * A021680 A299617 A201931
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Dec 01 2011
STATUS
approved