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Number of reduced words of length n in Coxeter group on 48 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
0

%I #7 Dec 30 2017 15:43:30

%S 1,48,2256,104904,4877472,226750560,10541488248,490066437936,

%T 22782847249104,1059158680807752,49239548471206560,

%U 2289112271116376928,106419233167075660536,4947355938259459431984,229999127520543810796752

%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)^3 = 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_03">Index entries for linear recurrences with constant coefficients</a>, signature (46, 46, -1081).

%F G.f.: (t^3 + 2*t^2 + 2*t + 1)/(1081*t^3 - 46*t^2 - 46*t + 1)

%t coxG[{3,1081,-46}] (* The coxG program is at A169452 *) (* or *) LinearRecurrence[{46,46,-1081},{1,48,2256,104904},30] (* _Harvey P. Dale_, Dec 30 2017 *)

%K nonn

%O 0,2

%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009