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A197840
Decimal expansion of greatest x having x^2-4x=-cos(x).
3
4, 1, 3, 2, 5, 7, 3, 4, 7, 0, 7, 5, 3, 8, 6, 8, 3, 0, 8, 1, 9, 8, 4, 4, 1, 7, 0, 5, 3, 6, 2, 8, 0, 6, 1, 2, 1, 0, 5, 5, 1, 8, 5, 3, 1, 5, 3, 8, 1, 1, 1, 8, 0, 1, 1, 7, 2, 6, 0, 4, 0, 6, 9, 4, 2, 3, 3, 7, 8, 0, 0, 3, 2, 1, 2, 4, 7, 6, 1, 8, 2, 7, 0, 6, 7, 2, 4, 2, 3, 5, 8, 4, 3, 9, 1, 8, 1, 4, 3
OFFSET
1,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: 0.25839214437159967402757423807386027526101...
greatest x: 4.13257347075386830819844170536280612105...
MATHEMATICA
a = 1; b = -4; c = -1;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 5}]
r1 = x /. FindRoot[f[x] == g[x], {x, -4.2, -4.1}, WorkingPrecision -> 110]
RealDigits[r1] (* A197839 *)
r2 = x /. FindRoot[f[x] == g[x], {x, 4.1, 4.2}, WorkingPrecision -> 110]
RealDigits[r2] (* A197840 *)
CROSSREFS
Cf. A197737.
Sequence in context: A348566 A021246 A301907 * A360995 A344439 A342403
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 20 2011
STATUS
approved