cp's OEIS Frontend

A170290 Number of reduced words of length n in Coxeter group on 41 generators S_i with relations (S_i)^2 = (S_i S_j)^41 = I.

%I A170290 #6 Nov 22 2016 12:00:17
%S A170290 1,41,1640,65600,2624000,104960000,4198400000,167936000000,
%T A170290 6717440000000,268697600000000,10747904000000000,429916160000000000,
%U A170290 17196646400000000000,687865856000000000000,27514634240000000000000
%N A170290 Number of reduced words of length n in Coxeter group on 41 generators S_i with relations (S_i)^2 = (S_i S_j)^41 = I.
%C A170290 The initial terms coincide with those of A170760, although the two sequences are eventually different.
%C A170290 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170290 <a href="/index/Rec#order_41">Index entries for linear recurrences with constant coefficients</a>, signature (39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, -780).
%F A170290 G.f. (t^41 + 2*t^40 + 2*t^39 + 2*t^38 + 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 +
%F A170290 2*t^33 + 2*t^32 + 2*t^31 + 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 +
%F A170290 2*t^25 + 2*t^24 + 2*t^23 + 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 +
%F A170290 2*t^17 + 2*t^16 + 2*t^15 + 2*t^14 + 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 +
%F A170290 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t +
%F A170290 1)/(780*t^41 - 39*t^40 - 39*t^39 - 39*t^38 - 39*t^37 - 39*t^36 - 39*t^35
%F A170290 - 39*t^34 - 39*t^33 - 39*t^32 - 39*t^31 - 39*t^30 - 39*t^29 - 39*t^28 -
%F A170290 39*t^27 - 39*t^26 - 39*t^25 - 39*t^24 - 39*t^23 - 39*t^22 - 39*t^21 -
%F A170290 39*t^20 - 39*t^19 - 39*t^18 - 39*t^17 - 39*t^16 - 39*t^15 - 39*t^14 -
%F A170290 39*t^13 - 39*t^12 - 39*t^11 - 39*t^10 - 39*t^9 - 39*t^8 - 39*t^7 -
%F A170290 39*t^6 - 39*t^5 - 39*t^4 - 39*t^3 - 39*t^2 - 39*t + 1)
%K A170290 nonn
%O A170290 0,2
%A A170290 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009