cp's OEIS Frontend

A170149 Number of reduced words of length n in Coxeter group on 44 generators S_i with relations (S_i)^2 = (S_i S_j)^38 = I.

%I A170149 #6 May 14 2017 17:42:27
%S A170149 1,44,1892,81356,3498308,150427244,6468371492,278139974156,
%T A170149 11960018888708,514280812214444,22114074925221092,950905221784506956,
%U A170149 40888924536733799108,1758223755079553361644,75603621468420794550692
%N A170149 Number of reduced words of length n in Coxeter group on 44 generators S_i with relations (S_i)^2 = (S_i S_j)^38 = I.
%C A170149 The initial terms coincide with those of A170763, although the two sequences are eventually different.
%C A170149 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170149 <a href="/index/Rec#order_38">Index entries for linear recurrences with constant coefficients</a>, signature (42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, -903).
%F A170149 G.f. (t^38 + 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 + 2*t^33 + 2*t^32 + 2*t^31 +
%F A170149 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 + 2*t^24 + 2*t^23 +
%F A170149 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*t^16 + 2*t^15 +
%F A170149 2*t^14 + 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 + 2*t^7 +
%F A170149 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(903*t^38 - 42*t^37 -
%F A170149 42*t^36 - 42*t^35 - 42*t^34 - 42*t^33 - 42*t^32 - 42*t^31 - 42*t^30 -
%F A170149 42*t^29 - 42*t^28 - 42*t^27 - 42*t^26 - 42*t^25 - 42*t^24 - 42*t^23 -
%F A170149 42*t^22 - 42*t^21 - 42*t^20 - 42*t^19 - 42*t^18 - 42*t^17 - 42*t^16 -
%F A170149 42*t^15 - 42*t^14 - 42*t^13 - 42*t^12 - 42*t^11 - 42*t^10 - 42*t^9 -
%F A170149 42*t^8 - 42*t^7 - 42*t^6 - 42*t^5 - 42*t^4 - 42*t^3 - 42*t^2 - 42*t + 1)
%K A170149 nonn
%O A170149 0,2
%A A170149 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009