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A075838
Decimal expansion of the solution to the donkey problem.
2
9, 5, 2, 8, 4, 7, 8, 6, 4, 6, 5, 4, 9, 4, 1, 9, 4, 7, 4, 4, 1, 3, 3, 3, 2, 1, 8, 5, 8, 0, 4, 8, 3, 3, 5, 1, 7, 4, 7, 5, 2, 1, 5, 6, 0, 8, 0, 6, 4, 0, 1, 6, 0, 6, 0, 9, 6, 7, 8, 2, 2, 7, 9, 9, 9, 7, 2, 7, 2, 1, 2, 0, 4, 9, 7, 8, 9, 7, 5, 1, 1, 3, 7, 8, 5, 8, 0, 8, 3, 1, 7, 3, 2, 3, 1, 5
OFFSET
0,1
LINKS
Dr. Math, Grazing Animals.
Marshall Fraser, A tale of two goats, Math. Mag., 55 (1982), 221-227. [N. J. A. Sloane, Jul 12 2011]
FORMULA
x: 4x*cos^2(x) + (1/2)Pi - 2x - sin(2x) = 0.
EXAMPLE
0.95284786465494194744133321858048335174752156080640...
MATHEMATICA
RealDigits[x /. FindRoot[4*x*Cos[x]^2 + Pi/2 - 2*x - Sin[2*x] == 0, {x, 1}, WorkingPrecision -> 120], 10, 105][[1]] (* Amiram Eldar, Apr 29 2023 *)
PROG
(PARI) solve(x=0, 1, 4*x*cos(x)^2 + Pi/2 - 2*x - sin(2*x)) \\ Michel Marcus, Sep 19 2017
CROSSREFS
KEYWORD
easy,nonn,cons
AUTHOR
Zak Seidov, Oct 17 2002
STATUS
approved