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A198842
Decimal expansion of x>0 satisfying x^2-4*cos(x)=-1.
2
1, 0, 2, 9, 7, 0, 4, 0, 0, 0, 7, 3, 6, 0, 5, 4, 5, 5, 8, 4, 1, 1, 6, 7, 9, 2, 6, 7, 9, 8, 2, 9, 0, 6, 9, 5, 8, 9, 4, 5, 5, 8, 8, 8, 3, 4, 8, 1, 5, 9, 5, 7, 8, 4, 0, 6, 8, 8, 0, 7, 9, 2, 9, 7, 4, 9, 5, 7, 2, 7, 6, 2, 9, 7, 4, 3, 4, 7, 2, 6, 5, 2, 4, 8, 3, 5, 7, 7, 1, 8, 8, 8, 9, 1, 0, 5, 9, 6, 9
OFFSET
1,3
COMMENTS
See A198755 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=1.0297040007360545584116792679829069589455888...
MATHEMATICA
a = 1; b = -4; c = -1;
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, 1.02, 1.03}, WorkingPrecision -> 110]
RealDigits[r] (* A198842 *)
CROSSREFS
Cf. A198755.
Sequence in context: A318969 A021775 A258501 * A016596 A201616 A197017
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 30 2011
STATUS
approved