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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)^7 = I.
0

%I #13 Dec 03 2025 17:11:30

%S 1,48,2256,106032,4983504,234224688,11008560336,517402334664,

%T 24317909676192,1142941752290400,53718262240589472,

%U 2524758319805916768,118663640772294032544,5577191104144368918624,262127981323573161732216

%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)^7 = 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_07">Index entries for linear recurrences with constant coefficients</a>, signature (46, 46, 46, 46, 46, 46, -1081).

%F G.f.: (t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(1081*t^7 - 46*t^6 - 46*t^5 - 46*t^4 - 46*t^3 - 46*t^2 - 46*t + 1).

%t coxG[{7,1081,-46}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Dec 10 2024 *)

%K nonn

%O 0,2

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