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%I #13 Mar 11 2024 20:53:35
%S 1,-3,5,-13,28,-73,164,-421,956,-2449,5572,-14269,32476,-83161,189284,
%T -484693,1103228,-2824993,6430084,-16465261,37477276,-95966569,
%U 218433572,-559334149,1273124156,-3260038321,7420311364,-19000895773,43248744028,-110745336313
%N Expansion of (-1+3*x+2*x^2-8*x^3+3*x^5-2*x^6-2*x^7+x^8) / ((x-1)*(x+1)*(x^2-2*x-1)*(x^2+2*x-1)).
%C Floretion Algebra Multiplication Program, FAMP Code: 4baseksigcycsumseq[A*B] with A = + 'i + .5'ii' + .5'jj' + .5'kk' + .5e and B = - .25'j + .25'k - .25j' + .25k' - .5'ii' - .25'ij' - .25'ik' - .25'ji' - .25'ki' - .5e; sumtype: (Y[15], *, sum/2)
%H Colin Barker, <a href="/A110225/b110225.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (0,7,0,-7,0,1).
%F a(n) = -5*A000129(n+1) +12*A000129(n) -1/2 +(-1)^n/2 +(-1)^n*A000129(n+1), if n>2. - _R. J. Mathar_, Nov 10 2009
%F a(n) = 7*a(n-2) - 7*a(n-4) + a(n-6) for n>8. - _Colin Barker_, May 16 2019
%o (PARI) Vec((1 - 3*x - 2*x^2 + 8*x^3 - 3*x^5 + 2*x^6 + 2*x^7 - x^8) / ((1 - x)*(1 + x)*(1 + 2*x - x^2)*(1 - 2*x - x^2)) + O(x^30)) \\ _Colin Barker_, May 16 2019
%K easy,sign
%O 0,2
%A _Creighton Dement_, Sep 06 2005