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A198992
Decimal expansion of x>0 satisfying 4*x^2-2*cos(x)=1.
2
7, 7, 8, 4, 5, 8, 8, 9, 9, 8, 1, 9, 6, 9, 4, 6, 8, 0, 4, 5, 3, 2, 2, 4, 8, 6, 5, 8, 4, 0, 5, 8, 9, 2, 7, 5, 2, 6, 5, 8, 4, 1, 2, 6, 2, 9, 3, 0, 8, 3, 3, 6, 3, 2, 4, 3, 8, 4, 7, 7, 2, 4, 6, 9, 3, 1, 6, 6, 9, 5, 8, 7, 3, 4, 2, 6, 8, 8, 6, 8, 5, 4, 3, 2, 6, 5, 8, 1, 0, 9, 2, 5, 4, 0, 4, 6, 3, 3, 4
OFFSET
0,1
COMMENTS
See A198755 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=0.77845889981969468045322486584058927526584126293...
MATHEMATICA
a = 4; b = -2; c = 1;
f[x_] := a*x^2 + b*Cos[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, .77, .78}, WorkingPrecision -> 110]
RealDigits[r] (* A198992 *)
CROSSREFS
Cf. A198755.
Sequence in context: A374837 A353973 A316139 * A201668 A021853 A349822
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 01 2011
STATUS
approved