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%I #16 Mar 06 2024 15:45:34
%S -1,1,2,2,9,9,4,-4,5,5,18,18,7,-7,8,8,27,27,10,-10,11,11,36,36,13,-13,
%T 14,14,45,45,16,-16,17,17,54,54,19,-19,20,20,63,63,22,-22,23,23,72,72,
%U 25,-25,26,26,81,81,28,-28,29,29,90,90,31,-31,32,32,99,99,34,-34,35,35,108,108,37,-37,38,38,117,117,40,-40,41,41,126
%N Expansion of (1-x-2*x^2-2*x^3-9*x^4-9*x^5-6*x^6+6*x^7-x^8-x^9-2*x^13+2*x^12) / (-x^12-1+2*x^6).
%C Floretion Algebra Multiplication Program, FAMP Code: 4kbasesigcycrokseq[ + .25'j - .25'k + .25j' - .25k' + .5'ii' + .25'ij' + .25'ik' + .25'ji' + .25'ki' + .5e]. See link to "Sequences in Context" for details on the "roktype" used.
%H Colin Barker, <a href="/A104681/b104681.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,2,0,0,0,0,0,-1).
%F For n>=0, a(6n+2)=a(6n+3)=6n+2; a(6n+5)=6n+5; a(6n+6)=-6n-6; a(6n+3)=a(6n+4)=9n+9.
%F a(n) = 2*a(n-6) - a(n-12) for n>13. - _Colin Barker_, May 14 2019
%o (PARI) -Vec((1 - x - 2*x^2 - 2*x^3 - 9*x^4 - 9*x^5 - 6*x^6 + 6*x^7 - x^8 - x^9 + 2*x^12 - 2*x^13) / ((1 - x)^2*(1 + x)^2*(1 - x + x^2)^2*(1 + x + x^2)^2) + O(x^65)) \\ _Colin Barker_, May 14 2019
%K sign
%O 0,3
%A _Creighton Dement_, Apr 22 2005