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A147776
Decimal expansion of z^(-3)+z^(-2)+z^(-1)+1+z+z^2+z^3, where z = exp(2*Pi*I/23).
0
5, 9, 9, 9, 7, 7, 9, 6, 7, 0, 2, 2, 5, 8, 8, 3, 8, 6, 0, 8, 7, 5, 9, 5, 3, 5, 2, 4, 5, 9, 2, 0, 6, 0, 3, 5, 5, 0, 0, 3, 2, 8, 9, 7, 0, 0, 5, 1, 7, 8, 1, 0, 6, 9, 7, 3, 5, 6, 1, 5, 8, 4, 4, 7, 5, 0, 5, 8, 6, 9, 2, 2, 4, 8, 5, 7, 7, 0, 9, 0, 4, 3, 4, 0, 3, 0, 8, 6, 3, 9, 7, 0, 6, 7, 2, 8, 8, 4, 7
OFFSET
1,1
FORMULA
7 - 56*sin(Pi/23)^2 + 112*sin(Pi/23)^4 - 64*sin(Pi/23)^6. - Charles R Greathouse IV, Mar 25 2014
EXAMPLE
5.9997796702258838608759535245920603550032897005178106973561...
MATHEMATICA
RealDigits[Total[Re[Exp[(2 Pi I)/23]^Range[-3, 3]]], 10, 120][[1]] (* Harvey P. Dale, Jan 02 2022 *)
PROG
(PARI) subst(Pol([-64, 112, -56, 7]), 'x, sin(Pi/23)^2) \\ Charles R Greathouse IV, Mar 25 2014
CROSSREFS
Cf. A147777.
Sequence in context: A055199 A147777 A086731 * A020846 A180014 A105643
KEYWORD
nonn,cons
AUTHOR
N. J. A. Sloane, May 03 2009, based on a posting to the Number Theory List by Nigel Boston, Apr 29 2009
STATUS
approved