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A197584
Decimal expansion of least x>0 having cos(Pi*x/3)=(cos(x/3))^2.
1
4, 5, 0, 4, 5, 7, 4, 9, 4, 1, 3, 6, 7, 2, 8, 7, 6, 5, 2, 0, 5, 1, 8, 4, 1, 7, 8, 8, 6, 5, 8, 8, 3, 4, 4, 7, 1, 4, 0, 9, 5, 4, 3, 3, 5, 9, 2, 1, 7, 0, 2, 3, 3, 7, 6, 9, 1, 5, 4, 9, 8, 3, 2, 7, 8, 1, 0, 0, 9, 0, 1, 3, 3, 8, 6, 6, 3, 5, 0, 2, 5, 2, 8, 5, 5, 1, 7, 5, 5, 1
OFFSET
1,1
FORMULA
Equals 3*A197515. - R. J. Mathar, Oct 18 2011
EXAMPLE
4.504574941367287652051841788658834471409543359217023376915498327810090...
MAPLE
fsolve(cos(Pi*x/3)-cos(x/3)^2, x=1..5) ; # R. J. Mathar, Oct 18 2011
PROG
(PARI) solve(x=4, 5, cos(Pi/3*x)-cos(x/3)^2) \\ Charles R Greathouse IV, Oct 18 2011
CROSSREFS
Cf. A197133.
Sequence in context: A366362 A199967 A021226 * A213440 A011286 A246927
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 16 2011
EXTENSIONS
Corrected by Charles R Greathouse IV, Oct 18 2011
STATUS
approved