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 A111915 Expansion of -x^2*(x-1)*(x^2-x+1)*(x+x^2+1)/(1-x^4+x^8). 3
 0, 0, 1, -1, 1, -1, 2, -2, 1, -1, 1, -1, 0, 0, -1, 1, -1, 1, -2, 2, -1, 1, -1, 1, 0, 0, 1, -1, 1, -1, 2, -2, 1, -1, 1, -1, 0, 0, -1, 1, -1, 1, -2, 2, -1, 1, -1, 1, 0, 0, 1, -1, 1, -1, 2, -2, 1, -1, 1, -1, 0, 0, -1, 1, -1, 1, -2, 2, -1, 1, -1, 1, 0, 0, 1, -1, 1, -1, 2, -2, 1, -1, 1, -1, 0, 0, -1, 1, -1, 1, -2, 2, -1, 1, -1, 1, 0, 0, 1, -1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,7 COMMENTS It appears that a(n) has period 24. This is true, as (1-x^4+x^8) is the cyclotomic polynomial for n=24. - Joerg Arndt, Feb 03 2017 LINKS Index entries for linear recurrences with constant coefficients, signature (0,0,0,1,0,0,0,-1). FORMULA G.f.: -x^2*(x-1)*(x^2-x+1)*(x+x^2+1)/(1-x^4+x^8). MATHEMATICA CoefficientList[Series[-x^2*(x - 1)*(x^2 - x + 1)*(x + x^2 + 1)/(1 - x^4 + x^8), {x, 0, 100}], x] (* Wesley Ivan Hurt, Feb 03 2017 *) PROG (PARI) a(n)=[0, 0, 1, -1, 1, -1, 2, -2, 1, -1, 1, -1, 0, 0, -1, 1, -1, 1, -2, 2, -1, 1, -1, 1][n%24+1] \\ Charles R Greathouse IV, Feb 03 2017 CROSSREFS Cf. A085846, A111912, A111913, A111914. Sequence in context: A343453 A051031 A181059 * A066520 A088526 A334091 Adjacent sequences:  A111912 A111913 A111914 * A111916 A111917 A111918 KEYWORD easy,less,sign AUTHOR Creighton Dement, Aug 20 2005 STATUS approved

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Last modified July 26 11:35 EDT 2021. Contains 346294 sequences. (Running on oeis4.)