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 A122605 Expansion of -x*(2*x - 1)*(2*x^2 - 1)*(x^3 + 2*x^2 - x - 1)/((x - 1)*(x^2 + x - 1)*(x^4 - 4*x^3 - 4*x^2 + x + 1)). 0
 1, 0, 0, 0, 0, 0, 0, -1, -1, -7, -8, -35, -44, -154, -208, -637, -910, -2548, -3808, -9996, -15504, -38760, -62015, -149225, -245135, -572010, -961125, -2186886, -3746886, -8348172, -14547183, -31842580, -56309764, -121415344, -217478888, -462925232, -838520240, -1765205473, -3228800413 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,10 LINKS Peter Steinbach, Golden fields: a case for the heptagon, Math. Mag. Vol. 70, No. 1, Feb. 1997, 22-31. Index entries for linear recurrences with constant coefficients, signature (1,6,-5,-10,6,4,-1). FORMULA a(0)=1, a(1)=a(2)=a(3)=a(4)=a(5)=a(6)=0; for n>6, a(n) = a(n-1) + 6*a(n-2) - 5*a(n-3) - 10*a(n-4) + 6*a(n-5) + 4*a(n-6) - a(n-7). - Harvey P. Dale, May 02 2011 G.f.: -x*(2*x-1)*(2*x^2-1)*(x^3+2*x^2-x-1)/((x-1)*(x^2+x-1)*(x^4-4*x^3-4*x^2+x+1)). - Colin Barker, Nov 08 2012 MATHEMATICA LinearRecurrence[{1, 6, -5, -10, 6, 4, -1}, {1, 0, 0, 0, 0, 0, 0}, 60] (* Harvey P. Dale, May 02 2011 *) CROSSREFS Cf. A066170. Sequence in context: A042875 A154745 A048064 * A037953 A296636 A041106 Adjacent sequences:  A122602 A122603 A122604 * A122606 A122607 A122608 KEYWORD sign,easy AUTHOR Roger L. Bagula and Gary W. Adamson, Sep 20 2006 EXTENSIONS Edited by N. J. A. Sloane, Feb 11 2007 Definition changed using Barker's g.f. by Bruno Berselli, Sep 19 2017 STATUS approved

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Last modified September 17 22:53 EDT 2019. Contains 327147 sequences. (Running on oeis4.)