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A192003
Row sums of array A187360: minimal polynomials of 2*cos(Pi/n) evaluated for x=1.
2
3, 1, 0, -1, -1, -2, -1, -1, -3, 1, 1, -2, 1, 1, -5, -1, -1, 1, -1, 1, 7, 1, 1, -2, -1, 1, -3, 1, -1, 1, -1, -1, -11, 1, 1, 1, 1, 1, 13, 1, -1, 1, -1, 1, 1, 1, 1, -2, -1, 1, -17, 1, -1, 1, 1, 1, 19, 1, 1, 1, 1, 1, 1, -1, 1, 1, -1, 1, -23, 1, 1, 1, 1, 1, -5, 1, 1, 1, -1, 1
OFFSET
1,1
FORMULA
a(n) = sum(A187360(n,m),m=0..A055034(n)), n>=1.
a(n) = C(n,x=1), with the minimal (monic and integer) polynomial C(n,x) of 2*cos(Pi/n).
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Wolfdieter Lang, Jul 14 2011
STATUS
approved