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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 (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..101.

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

Adjacent sequences:  A201410 A201411 A201412 * A201414 A201415 A201416

KEYWORD

nonn,cons

AUTHOR

Clark Kimberling, Dec 01 2011

STATUS

approved

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Last modified June 30 02:41 EDT 2022. Contains 354913 sequences. (Running on oeis4.)