%I #7 Aug 08 2017 11:39:15
%S 1,17,272,4216,65280,1009800,15620280,241617600,3737392200,
%T 57810713400,894227472000,13832085717000,213957412227000,
%U 3309535172520000,51192538485165000,791856215398035000,12248587087545600000
%N Number of reduced words of length n in Coxeter group on 17 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
%C The initial terms coincide with those of A170736, 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_03">Index entries for linear recurrences with constant coefficients</a>, signature (15, 15, -120).
%F G.f.: (t^3 + 2*t^2 + 2*t + 1)/(120*t^3 - 15*t^2 - 15*t + 1)
%t coxG[{3,120,-15}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Aug 08 2017 *)
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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