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A198369
Decimal expansion of least x having 4*x^2+4x=cos(x), negated.
3
1, 1, 0, 2, 3, 8, 4, 7, 4, 6, 2, 7, 9, 4, 3, 9, 5, 9, 5, 8, 0, 5, 8, 1, 8, 3, 6, 5, 8, 6, 7, 8, 8, 1, 3, 9, 4, 4, 9, 1, 9, 2, 4, 8, 4, 6, 4, 3, 3, 1, 7, 4, 9, 1, 7, 4, 3, 6, 5, 7, 0, 7, 8, 7, 4, 1, 5, 7, 9, 8, 0, 2, 0, 1, 8, 1, 3, 2, 9, 9, 5, 9, 2, 5, 9, 7, 1, 9, 5, 8, 2, 4, 5, 4, 1, 1, 4, 7, 8
OFFSET
1,4
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.1023847462794395958058183658678813...
greatest x: 0.203451325531925041555116805060611...
MATHEMATICA
a = 4; b = 4; c = 1;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -2, 1}]
r1 = x /. FindRoot[f[x] == g[x], {x, -1.2, -1.1}, WorkingPrecision -> 110]
RealDigits[r1] (* A198369 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .20, .21}, WorkingPrecision -> 110]
RealDigits[r2] (* A198370 *)
PROG
(PARI) solve(x=-2, -1, 4*x^2+4*x-cos(x)) \\ Charles R Greathouse IV, Apr 19 2026
CROSSREFS
Cf. A197737.
Sequence in context: A100869 A110142 A158928 * A390959 A193731 A193975
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 24 2011
STATUS
approved