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A199721
Decimal expansion of x>0 satisfying x^2-x*cos(x)=2*sin(x).
2
1, 4, 6, 4, 3, 3, 5, 1, 0, 3, 8, 6, 8, 0, 6, 7, 6, 6, 9, 6, 2, 3, 7, 2, 0, 4, 7, 8, 4, 2, 0, 4, 0, 8, 3, 7, 6, 2, 4, 9, 2, 5, 7, 4, 8, 6, 5, 8, 7, 2, 1, 7, 0, 0, 0, 4, 2, 3, 4, 7, 0, 1, 5, 6, 4, 2, 9, 2, 1, 9, 5, 7, 5, 8, 3, 4, 2, 4, 6, 0, 5, 7, 9, 4, 7, 6, 4, 9, 5, 8, 0, 7, 8, 8, 8, 3, 2, 1, 0
OFFSET
1,2
COMMENTS
See A199597 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=1.46433510386806766962372047842040837624925...
MATHEMATICA
a = 1; b = -1; c = 2;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -Pi, Pi}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]
RealDigits[r] (* A199721 *)
CROSSREFS
Cf. A199597.
Sequence in context: A133587 A204693 A204817 * A349942 A187147 A128633
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 09 2011
STATUS
approved