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 A140885 Triangle T(n,k) read by rows: the coefficient [x^k] ( Phi(n,x)+x^n*Phi(n,1/x)) related to cyclotomic polynomials Phi(n,x). 0
 0, 0, 0, 1, 2, 1, 1, 2, 2, 1, 1, 0, 2, 0, 1, 1, 2, 2, 2, 2, 1, 1, -1, 1, 0, 1, -1, 1, 1, 2, 2, 2, 2, 2, 2, 1, 1, 0, 0, 0, 2, 0, 0, 0, 1, 1, 0, 0, 2, 0, 0, 2, 0, 0, 1, 1, -1, 1, -1, 1, 0, 1, -1, 1, -1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 0, -1, 0, 1, 0, 0, 0, 1, 0, -1, 0, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, -1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS Row sums are: 0, 0, 4, 6, 4, 10, 2, 14, 4, 6, 2, 22, 2, 26, 2, 2, 4, 34, 2, 38, 2,... LINKS FORMULA T(n,k) = T(n,n-k) . EXAMPLE 0; # x+x^0*(1/x) = x+1/x 0, 0; # x-1+x*(1/x-1) = 0 1, 2, 1; # x+1+x^2*(1/x+1) = 1+2*x+x^2 1, 2, 2, 1; 1, 0, 2, 0, 1; 1, 2, 2, 2, 2, 1; 1, -1, 1, 0, 1, -1, 1; 1, 2, 2, 2, 2, 2, 2, 1; 1, 0, 0, 0, 2, 0, 0, 0, 1; 1, 0, 0, 2, 0, 0, 2, 0, 0, 1; 1, -1, 1, -1, 1, 0, 1, -1, 1, -1, 1; MATHEMATICA Clear[p, x, n, m, a]; p[x_, n_] := Cyclotomic[n, x] + ExpandAll[x^n*Cyclotomic[n, 1/x]]; Table[p[x, n], {n, 0, 10}]; a = Table[CoefficientList[p[x, n], x], {n, 0, 10}]; Flatten[a] CROSSREFS Cf. A013595. Sequence in context: A284593 A190672 A242998 * A064286 A002471 A218622 Adjacent sequences:  A140882 A140883 A140884 * A140886 A140887 A140888 KEYWORD tabl,sign AUTHOR Roger L. Bagula and Gary W. Adamson, Jul 22 2008 EXTENSIONS All entries replaced to comply with the definition and examples - The Assoc. Eds. of the OEIS, Oct 12 2010 STATUS approved

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