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A199171
Decimal expansion of x>0 satisfying x^2+x*cos(x)=1.
2
6, 8, 5, 1, 7, 4, 1, 3, 3, 8, 5, 4, 5, 0, 3, 1, 8, 7, 8, 9, 5, 2, 1, 1, 5, 3, 0, 6, 3, 8, 4, 5, 8, 7, 0, 9, 5, 9, 1, 7, 8, 5, 9, 1, 8, 9, 1, 9, 8, 8, 6, 0, 5, 2, 8, 0, 6, 6, 8, 3, 2, 7, 1, 3, 1, 9, 7, 0, 8, 5, 1, 2, 4, 4, 7, 2, 1, 1, 5, 1, 1, 4, 8, 5, 0, 0, 8, 6, 8, 4, 1, 0, 2, 7, 8, 8, 4, 2, 6
OFFSET
0,1
COMMENTS
See A199170 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
negative: -1.19835984451866026826502160343030898927268...
positive: 0.685174133854503187895211530638458709591...
MATHEMATICA
a = 1; b = 1; c = 1;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -2 Pi, 2 Pi}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -1.2, -1.1}, WorkingPrecision -> 110]
RealDigits[r] (* A199170 *)
r = x /. FindRoot[f[x] == g[x], {x, .68, .69}, WorkingPrecision -> 110]
RealDigits[r] (* A199171 *)
CROSSREFS
Cf. A199170.
Sequence in context: A123092 A209283 A209285 * A323737 A374883 A350860
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 03 2011
STATUS
approved