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%I #8 Jul 07 2019 16:25:44
%S 1,17,272,4352,69632,1114112,17825792,285212672,4563402616,
%T 73014439680,1168231000200,18691695448320,299067118295040,
%U 4785073750671360,76561177737953280,1224978807442636800,19599660337248356280
%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)^8 = 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_08">Index entries for linear recurrences with constant coefficients</a>, signature (15, 15, 15, 15, 15, 15, 15, -120).
%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)/(120*t^8 -
%F 15*t^7 - 15*t^6 - 15*t^5 - 15*t^4 - 15*t^3 - 15*t^2 - 15*t + 1)
%t coxG[{8,120,-15}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Jul 07 2019 *)
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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