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A198811
Decimal expansion of x>0 satisfying x^2+2*cos(x)=4.
2
2, 3, 1, 3, 5, 8, 9, 3, 4, 9, 0, 4, 8, 4, 8, 7, 9, 2, 2, 4, 4, 5, 3, 0, 4, 1, 3, 3, 6, 6, 6, 6, 7, 2, 8, 0, 7, 6, 1, 5, 6, 6, 4, 7, 2, 0, 7, 2, 0, 6, 7, 7, 3, 7, 5, 2, 1, 7, 0, 4, 8, 3, 6, 4, 1, 9, 2, 1, 9, 6, 8, 8, 7, 1, 5, 5, 4, 2, 7, 3, 4, 2, 5, 0, 0, 0, 1, 1, 5, 7, 7, 6, 3, 7, 2, 3, 4, 8, 9
OFFSET
1,1
COMMENTS
See A198755 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=2.3135893490484879224453041336666...
MATHEMATICA
a = 1; b = 2; c = 4;
f[x_] := a*x^2 + b*Cos[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, 2.3, 2.4}, WorkingPrecision -> 110]
RealDigits[r] (* A198811 *)
CROSSREFS
Cf. A198755.
Sequence in context: A194762 A054250 A193923 * A067337 A180091 A047973
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 30 2011
STATUS
approved