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%I #8 Apr 05 2022 10:53:37
%S 1,15,210,2940,41160,576240,8067360,112943040,1581202455,22136832900,
%T 309915640125,4338818675100,60743457438300,850408347952800,
%U 11905716084771600,166680014174856000,2333520044280745320
%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)^8 = 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_08">Index entries for linear recurrences with constant coefficients</a>, signature (13, 13, 13, 13, 13, 13, 13, -91).
%F G.f. (t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(91*t^8 -
%F 13*t^7 - 13*t^6 - 13*t^5 - 13*t^4 - 13*t^3 - 13*t^2 - 13*t + 1)
%t coxG[{8,91,-13}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Apr 05 2022 *)
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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