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A199189
Decimal expansion of x>0 satisfying 2*x^2+x*cos(x)=1.
4
5, 2, 2, 9, 4, 5, 9, 4, 6, 1, 1, 3, 1, 1, 1, 7, 3, 7, 2, 4, 7, 6, 2, 3, 8, 3, 6, 3, 5, 9, 8, 1, 1, 2, 3, 7, 1, 3, 9, 7, 3, 4, 5, 2, 5, 8, 0, 0, 2, 6, 0, 5, 9, 9, 0, 2, 3, 1, 1, 5, 7, 6, 4, 5, 8, 7, 4, 4, 7, 0, 8, 0, 0, 7, 9, 9, 6, 3, 1, 5, 6, 5, 3, 7, 1, 0, 3, 2, 7, 5, 4, 8, 5, 0, 6, 5, 8, 0, 1
OFFSET
0,1
COMMENTS
See A199170 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
negative: -0.883330197195891938925896450885677107...
positive: 0.522945946113111737247623836359811237139...
MATHEMATICA
a = 2; b = 1; c = 1;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -.84, -.83}, WorkingPrecision -> 110]
RealDigits[r] (* A199188 *)
r = x /. FindRoot[f[x] == g[x], {x, .52, .53}, WorkingPrecision -> 110]
RealDigits[r] (* A199189 *)
CROSSREFS
Cf. A199170.
Sequence in context: A200645 A011411 A201328 * A145438 A354197 A346040
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 04 2011
STATUS
approved