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 A192004 Alternating row sums of array A187360: minimal polynomial of 2*cos(pi/n) evaluated for x=-1. 2
 1, -1, -2, -1, 1, -2, 1, -1, 1, 1, 1, -2, 1, 1, 1, -1, 1, 1, 1, 1, 1, 1, 1, -2, 1, 1, 1, 1, 1, 1, 1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS FORMULA a(n) = sum(((-1)^m)*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 Cf. A055034, A192003. Sequence in context: A183017 A183014 A030382 * A120889 A092523 A120891 Adjacent sequences:  A192001 A192002 A192003 * A192005 A192006 A192007 KEYWORD sign,easy AUTHOR Wolfdieter Lang, Jul 14 2011 STATUS approved

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