cp's OEIS Frontend

A170211 Number of reduced words of length n in Coxeter group on 10 generators S_i with relations (S_i)^2 = (S_i S_j)^40 = I.

%I A170211 #6 Nov 22 2016 15:14:51
%S A170211 1,10,90,810,7290,65610,590490,5314410,47829690,430467210,3874204890,
%T A170211 34867844010,313810596090,2824295364810,25418658283290,
%U A170211 228767924549610,2058911320946490,18530201888518410,166771816996665690
%N A170211 Number of reduced words of length n in Coxeter group on 10 generators S_i with relations (S_i)^2 = (S_i S_j)^40 = I.
%C A170211 The initial terms coincide with those of A003952, although the two sequences are eventually different.
%C A170211 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170211 <a href="/index/Rec#order_40">Index entries for linear recurrences with constant coefficients</a>, signature (8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, -36).
%F A170211 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 A170211 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 A170211 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 A170211 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 A170211 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t +
%F A170211 1)/(36*t^40 - 8*t^39 - 8*t^38 - 8*t^37 - 8*t^36 - 8*t^35 - 8*t^34 -
%F A170211 8*t^33 - 8*t^32 - 8*t^31 - 8*t^30 - 8*t^29 - 8*t^28 - 8*t^27 - 8*t^26 -
%F A170211 8*t^25 - 8*t^24 - 8*t^23 - 8*t^22 - 8*t^21 - 8*t^20 - 8*t^19 - 8*t^18 -
%F A170211 8*t^17 - 8*t^16 - 8*t^15 - 8*t^14 - 8*t^13 - 8*t^12 - 8*t^11 - 8*t^10 -
%F A170211 8*t^9 - 8*t^8 - 8*t^7 - 8*t^6 - 8*t^5 - 8*t^4 - 8*t^3 - 8*t^2 - 8*t + 1)
%K A170211 nonn
%O A170211 0,2
%A A170211 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009