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A198110
Decimal expansion of x>0 having 2*x^2=cos(x).
2
6, 3, 4, 5, 5, 9, 9, 4, 5, 5, 2, 6, 6, 2, 2, 7, 4, 0, 0, 6, 7, 7, 6, 8, 3, 4, 3, 7, 6, 9, 8, 5, 4, 4, 8, 0, 3, 0, 7, 5, 7, 1, 6, 7, 8, 2, 2, 5, 1, 8, 8, 3, 6, 2, 1, 7, 7, 0, 5, 1, 5, 4, 1, 6, 2, 5, 6, 9, 3, 7, 6, 9, 2, 8, 9, 1, 9, 5, 4, 3, 1, 2, 9, 7, 3, 0, 1, 4, 0, 1, 9, 5, 5, 1, 3, 1, 8, 3, 1
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=0.6345599455266227400677683437698...
MATHEMATICA
a = 2; b = 0; c = 1;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 1}]
r = x /. FindRoot[f[x] == g[x], {x, 0.63, 0.64}, WorkingPrecision -> 110]
RealDigits[r] (* A198110 *)
CROSSREFS
Cf. A197737.
Sequence in context: A167052 A222230 A365066 * A377962 A290795 A197577
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 21 2011
STATUS
approved