cp's OEIS Frontend

A170248 Number of reduced words of length n in Coxeter group on 47 generators S_i with relations (S_i)^2 = (S_i S_j)^40 = I.

%I A170248 #6 Nov 22 2016 15:33:56
%S A170248 1,47,2162,99452,4574792,210440432,9680259872,445291954112,
%T A170248 20483429889152,942237774900992,43342937645445632,1993775131690499072,
%U A170248 91713656057762957312,4218828178657096036352,194066096218226417672192
%N A170248 Number of reduced words of length n in Coxeter group on 47 generators S_i with relations (S_i)^2 = (S_i S_j)^40 = I.
%C A170248 The initial terms coincide with those of A170766, although the two sequences are eventually different.
%C A170248 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170248 <a href="/index/Rec#order_40">Index entries for linear recurrences with constant coefficients</a>, signature (44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, -990).
%F A170248 G.f. (t^40 + 2*t^39 + 2*t^38 + 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 + 2*t^33 +
%F A170248 2*t^32 + 2*t^31 + 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 +
%F A170248 2*t^24 + 2*t^23 + 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 +
%F A170248 2*t^16 + 2*t^15 + 2*t^14 + 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 +
%F A170248 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t +
%F A170248 1)/(1035*t^40 - 45*t^39 - 45*t^38 - 45*t^37 - 45*t^36 - 45*t^35 -
%F A170248 45*t^34 - 45*t^33 - 45*t^32 - 45*t^31 - 45*t^30 - 45*t^29 - 45*t^28 -
%F A170248 45*t^27 - 45*t^26 - 45*t^25 - 45*t^24 - 45*t^23 - 45*t^22 - 45*t^21 -
%F A170248 45*t^20 - 45*t^19 - 45*t^18 - 45*t^17 - 45*t^16 - 45*t^15 - 45*t^14 -
%F A170248 45*t^13 - 45*t^12 - 45*t^11 - 45*t^10 - 45*t^9 - 45*t^8 - 45*t^7 -
%F A170248 45*t^6 - 45*t^5 - 45*t^4 - 45*t^3 - 45*t^2 - 45*t + 1)
%K A170248 nonn
%O A170248 0,2
%A A170248 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009