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A201410
Decimal expansion of least x satisfying 4*x^2 = sec(x) and 0 < x < Pi.
3
5, 3, 9, 8, 6, 1, 0, 8, 3, 9, 1, 2, 7, 7, 8, 4, 4, 3, 6, 3, 0, 6, 7, 3, 7, 3, 2, 7, 3, 2, 2, 8, 0, 7, 1, 4, 8, 0, 6, 2, 4, 1, 1, 2, 0, 9, 8, 1, 6, 0, 0, 5, 5, 4, 0, 8, 2, 8, 9, 8, 5, 4, 6, 1, 6, 0, 8, 1, 4, 4, 0, 2, 1, 2, 2, 0, 9, 8, 5, 5, 6, 0, 8, 2, 7, 8, 7, 3, 2, 0, 6, 5, 3, 0, 5, 9, 8, 3, 0
OFFSET
0,1
COMMENTS
See A201397 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: 0.53986108391277844363067373273228071480624...
greatest: 1.451925722123287999446946604502079960054...
MATHEMATICA
a = 4; 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, .5, .6}, WorkingPrecision -> 110]
RealDigits[r] (* A201410 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]
RealDigits[r] (* A201411 *)
CROSSREFS
Cf. A201397.
Sequence in context: A086970 A224511 A201938 * A332528 A019955 A296345
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Dec 01 2011
STATUS
approved