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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

%I

%S 1,0,0,0,0,0,0,-1,-1,-7,-8,-35,-44,-154,-208,-637,-910,-2548,-3808,

%T -9996,-15504,-38760,-62015,-149225,-245135,-572010,-961125,-2186886,

%U -3746886,-8348172,-14547183,-31842580,-56309764,-121415344,-217478888,-462925232,-838520240,-1765205473,-3228800413

%N 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)).

%H Peter Steinbach, <a href="http://www.jstor.org/stable/2691048">Golden fields: a case for the heptagon</a>, Math. Mag. Vol. 70, No. 1, Feb. 1997, 22-31.

%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1,6,-5,-10,6,4,-1).

%F 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

%F 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

%t LinearRecurrence[{1,6,-5,-10,6,4,-1},{1,0,0,0,0,0,0},60] (* _Harvey P. Dale_, May 02 2011 *)

%Y Cf. A066170.

%K sign,easy

%O 1,10

%A _Roger L. Bagula_ and _Gary W. Adamson_, Sep 20 2006

%E Edited by _N. J. A. Sloane_, Feb 11 2007

%E Definition changed using Barker's g.f. by _Bruno Berselli_, Sep 19 2017

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Last modified October 15 04:33 EDT 2019. Contains 328026 sequences. (Running on oeis4.)