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A198356
Decimal expansion of greatest x having 4*x^2+x=4*cos(x).
3
7, 4, 2, 4, 3, 7, 4, 8, 8, 9, 6, 5, 6, 0, 3, 3, 7, 8, 5, 1, 7, 2, 4, 5, 5, 3, 0, 1, 6, 4, 3, 2, 6, 3, 5, 3, 2, 0, 2, 8, 5, 6, 2, 4, 8, 9, 8, 5, 8, 2, 2, 6, 9, 0, 9, 3, 8, 1, 9, 4, 5, 2, 2, 9, 3, 3, 6, 2, 8, 9, 1, 7, 9, 5, 7, 6, 0, 6, 0, 6, 8, 0, 2, 1, 5, 9, 5, 3, 1, 4, 5, 8, 7, 7, 4, 9, 8, 8
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -0.91555432657358705292706966750136951...
greatest x: 0.7424374889656033785172455301643263...
MATHEMATICA
a = 4; b = 1; c = 4;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 1}]
r1 = x /. FindRoot[f[x] == g[x], {x, -1, -.9}, WorkingPrecision -> 110]
RealDigits[r1] (* A198355 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .74, .75}, WorkingPrecision -> 110]
RealDigits[r2] (* A198356 *)
CROSSREFS
Cf. A197737.
Sequence in context: A071185 A373018 A165244 * A377753 A254349 A019608
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 24 2011
STATUS
approved