cp's OEIS Frontend

A170198 Number of reduced words of length n in Coxeter group on 45 generators S_i with relations (S_i)^2 = (S_i S_j)^39 = I.

%I A170198 #6 Nov 22 2016 16:03:46
%S A170198 1,45,1980,87120,3833280,168664320,7421230080,326534123520,
%T A170198 14367501434880,632170063134720,27815482777927680,1223881242228817920,
%U A170198 53850774658067988480,2369434084954991493120,104255099738019625697280
%N A170198 Number of reduced words of length n in Coxeter group on 45 generators S_i with relations (S_i)^2 = (S_i S_j)^39 = I.
%C A170198 The initial terms coincide with those of A170764, although the two sequences are eventually different.
%C A170198 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170198 <a href="/index/Rec#order_39">Index entries for linear recurrences with constant coefficients</a>, signature (43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, -946).
%F A170198 G.f. (t^39 + 2*t^38 + 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 + 2*t^33 + 2*t^32 +
%F A170198 2*t^31 + 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 + 2*t^24 +
%F A170198 2*t^23 + 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*t^16 +
%F A170198 2*t^15 + 2*t^14 + 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 +
%F A170198 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(946*t^39 -
%F A170198 43*t^38 - 43*t^37 - 43*t^36 - 43*t^35 - 43*t^34 - 43*t^33 - 43*t^32 -
%F A170198 43*t^31 - 43*t^30 - 43*t^29 - 43*t^28 - 43*t^27 - 43*t^26 - 43*t^25 -
%F A170198 43*t^24 - 43*t^23 - 43*t^22 - 43*t^21 - 43*t^20 - 43*t^19 - 43*t^18 -
%F A170198 43*t^17 - 43*t^16 - 43*t^15 - 43*t^14 - 43*t^13 - 43*t^12 - 43*t^11 -
%F A170198 43*t^10 - 43*t^9 - 43*t^8 - 43*t^7 - 43*t^6 - 43*t^5 - 43*t^4 - 43*t^3 -
%F A170198 43*t^2 - 43*t + 1)
%K A170198 nonn
%O A170198 0,2
%A A170198 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009