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A198841
Decimal expansion of x>0 satisfying x^2-4*cos(x)=4.
2
1, 7, 8, 0, 1, 1, 7, 2, 2, 3, 4, 1, 3, 3, 4, 6, 8, 8, 9, 5, 9, 0, 3, 8, 5, 8, 7, 8, 9, 0, 2, 8, 3, 5, 8, 8, 2, 5, 4, 6, 2, 0, 1, 9, 4, 0, 3, 4, 4, 7, 7, 3, 5, 4, 7, 0, 5, 6, 8, 9, 9, 7, 1, 0, 4, 6, 8, 8, 4, 3, 4, 3, 5, 8, 3, 2, 6, 7, 0, 9, 7, 7, 0, 2, 8, 8, 5, 3, 0, 2, 8, 5, 8, 8, 8, 7, 2, 4, 0
OFFSET
1,2
COMMENTS
See A198755 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=1.780117223413346889590385878902835882546201940...
MATHEMATICA
a = 1; b = -4; 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, 1.7, 1.8}, WorkingPrecision -> 110]
RealDigits[r] (* A198841 *)
CROSSREFS
Cf. A198755.
Sequence in context: A320914 A155846 A221114 * A332634 A330652 A181438
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 30 2011
STATUS
approved