%I #8 Nov 26 2016 16:33:14
%S 1,3,6,12,24,48,96,192,384,765,1524,3039,6060,12084,24096,48048,95808,
%T 191040,380934,759585,1514616,3020151,6022194,12008280,23944560,
%U 47745552,95204832,189838836,378539436,754809225,1505092764,3001161291
%N Number of reduced words of length n in Coxeter group on 3 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.
%C The initial terms coincide with those of A003945, 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 (2, -1, 2, -1, 2, -1, 2, -1).
%F G.f. (t^8 + t^7 + t^6 + t^5 + t^4 + t^3 + t^2 + t + 1)/(t^8 - 2*t^7 + t^6 - 2*t^5
%F + t^4 - 2*t^3 + t^2 - 2*t + 1)
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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