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A198123
Decimal expansion of greatest x having 2*x^2-4x=-cos(x).
3
2, 1, 2, 3, 6, 3, 3, 3, 3, 4, 5, 1, 9, 9, 8, 2, 3, 9, 4, 1, 9, 8, 7, 7, 0, 2, 4, 6, 4, 1, 1, 0, 6, 1, 4, 6, 7, 9, 0, 2, 8, 1, 7, 3, 9, 1, 0, 9, 6, 7, 7, 3, 4, 1, 9, 2, 3, 6, 9, 5, 8, 2, 4, 7, 6, 4, 8, 6, 0, 7, 5, 3, 6, 7, 3, 0, 0, 4, 0, 4, 0, 3, 9, 0, 5, 4, 2, 9, 6, 4, 9, 6, 8, 8, 6, 0, 6, 3, 6
OFFSET
1,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: 0.27932077973816506128059339665539554...
greatest x: 2.123633334519982394198770246411061...
MATHEMATICA
a = 2; b = -4; c = -1;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 3}]
r1 = x /. FindRoot[f[x] == g[x], {x, .27, .28}, WorkingPrecision -> 110]
RealDigits[r1](* A198122 *)
r2 = x /. FindRoot[f[x] == g[x], {x, 2.1, 2.2}, WorkingPrecision -> 110]
RealDigits[r2](* A198123 *)
CROSSREFS
Cf. A197737.
Sequence in context: A156565 A156693 A156564 * A106576 A301336 A128474
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 21 2011
STATUS
approved