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%I #6 Nov 23 2016 22:09:11
%S 1,15,210,2940,41160,576240,8067360,112943040,1581202560,22136835735,
%T 309915698820,4338819763005,60743476395420,850408665522780,
%U 11905721261135520,166680096869329680,2333521345158669120
%N Number of reduced words of length n in Coxeter group on 15 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.
%C The initial terms coincide with those of A170734, 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_09">Index entries for linear recurrences with constant coefficients</a>, signature (13, 13, 13, 13, 13, 13, 13, 13, -91).
%F G.f. (t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t +
%F 1)/(91*t^9 - 13*t^8 - 13*t^7 - 13*t^6 - 13*t^5 - 13*t^4 - 13*t^3 -
%F 13*t^2 - 13*t + 1)
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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