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A201407 Decimal expansion of greatest x satisfying 2*x^2 = sec(x) and 0 < x < Pi. 3
1, 2, 3, 9, 0, 8, 2, 6, 2, 0, 9, 2, 7, 5, 8, 1, 9, 1, 8, 7, 1, 5, 1, 0, 9, 2, 3, 9, 9, 0, 1, 9, 8, 5, 5, 3, 8, 0, 5, 9, 7, 0, 2, 3, 5, 0, 1, 4, 3, 6, 4, 9, 1, 5, 7, 2, 1, 6, 0, 1, 7, 3, 8, 1, 6, 9, 8, 5, 5, 6, 7, 6, 8, 9, 1, 6, 6, 6, 7, 5, 4, 8, 4, 3, 7, 7, 8, 8, 0, 8, 7, 6, 7, 7, 9, 7, 5, 9, 0 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

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

LINKS

Table of n, a(n) for n=1..99.

EXAMPLE

least:  0.892874306058961124447371969018677514...

greatest: 1.2390826209275819187151092399019855...

MATHEMATICA

a = 2; 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, .8, 1}, WorkingPrecision -> 110]

RealDigits[r]   (* A201406 *)

r = x /. FindRoot[f[x] == g[x], {x, 1.2, 1.3}, WorkingPrecision -> 110]

RealDigits[r]   (* A201407 *)

CROSSREFS

Cf. A201397.

Sequence in context: A114020 A011163 A155983 * A109197 A021811 A280987

Adjacent sequences:  A201404 A201405 A201406 * A201408 A201409 A201410

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Dec 01 2011

STATUS

approved

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Last modified October 22 07:53 EDT 2021. Contains 348160 sequences. (Running on oeis4.)