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%I #11 Sep 04 2022 08:35:36
%S 1,48,2256,106032,4983504,234224688,11008560336,517402335792,
%T 24317909781096,1142941759658496,53718262701458688,
%U 2524758346851499008,118663642296518664960,5577191187677793197568,262127985808702829674752
%N Number of reduced words of length n in Coxeter group on 48 generators S_i with relations (S_i)^2 = (S_i S_j)^8 = I.
%C The initial terms coincide with those of A170767, although the two sequences are eventually different.
%C Computed with MAGMA using commands similar to those used to compute A154638.
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (46, 46, 46, 46, 46, 46, 46, -1081).
%F G.f.: (t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(1081*t^8 - 46*t^7 - 46*t^6 - 46*t^5 - 46*t^4 - 46*t^3 - 46*t^2 - 46*t + 1).
%F a(n) = -1081*a(n-8) + 46*Sum_{k=1..7} a(n-k). - _Wesley Ivan Hurt_, Sep 04 2022
%t With[{num=Total[2t^Range[7]]+t^8+1,den=Total[-46 t^Range[7]]+1081t^8+ 1}, CoefficientList[Series[num/den,{t,0,30}],t]] (* _Harvey P. Dale_, Jul 27 2011 *)
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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