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A198212
Decimal expansion of x>0 having 3*x^2=2*cos(x).
2
7, 1, 0, 7, 9, 4, 6, 8, 7, 7, 7, 4, 4, 6, 5, 3, 3, 7, 8, 4, 6, 7, 3, 5, 2, 9, 1, 4, 7, 5, 3, 2, 7, 5, 9, 4, 3, 3, 2, 3, 7, 4, 4, 0, 8, 7, 1, 7, 6, 4, 0, 0, 4, 0, 2, 2, 4, 3, 3, 1, 6, 6, 1, 9, 5, 3, 8, 0, 2, 0, 4, 7, 2, 3, 1, 7, 4, 4, 8, 3, 4, 5, 1, 0, 6, 0, 6, 4, 8, 9, 0, 1, 9, 2, 3, 9, 8, 8, 3
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
x=0.7107946877744653378467352914753275...
MATHEMATICA
a = 3; b = 0; c = 2;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 1}]
r = x /. FindRoot[f[x] == g[x], {x, 0.71, 0.72}, WorkingPrecision -> 110]
RealDigits[r] (* A198212 *)
CROSSREFS
Cf. A197737.
Sequence in context: A198611 A298853 A351213 * A217245 A154098 A324007
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 22 2011
STATUS
approved