cp's OEIS Frontend

A169488 Number of reduced words of length n in Coxeter group on 43 generators S_i with relations (S_i)^2 = (S_i S_j)^33 = I.

%I A169488 #8 Nov 26 2016 07:27:29
%S A169488 1,43,1806,75852,3185784,133802928,5619722976,236028364992,
%T A169488 9913191329664,416354035845888,17486869505527296,734448519232146432,
%U A169488 30846837807750150144,1295567187925506306048,54413821892871264854016
%N A169488 Number of reduced words of length n in Coxeter group on 43 generators S_i with relations (S_i)^2 = (S_i S_j)^33 = I.
%C A169488 The initial terms coincide with those of A170762, although the two sequences are eventually different.
%C A169488 Computed with MAGMA using commands similar to those used to compute A154638.
%H A169488 <a href="/index/Rec#order_33">Index entries for linear recurrences with constant coefficients</a>, signature (41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, 41, -861).
%F A169488 G.f. (t^33 + 2*t^32 + 2*t^31 + 2*t^30 + 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 +
%F A169488 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 A169488 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 A169488 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 A169488 1)/(861*t^33 - 41*t^32 - 41*t^31 - 41*t^30 - 41*t^29 - 41*t^28 - 41*t^27
%F A169488 - 41*t^26 - 41*t^25 - 41*t^24 - 41*t^23 - 41*t^22 - 41*t^21 - 41*t^20 -
%F A169488 41*t^19 - 41*t^18 - 41*t^17 - 41*t^16 - 41*t^15 - 41*t^14 - 41*t^13 -
%F A169488 41*t^12 - 41*t^11 - 41*t^10 - 41*t^9 - 41*t^8 - 41*t^7 - 41*t^6 - 41*t^5
%F A169488 - 41*t^4 - 41*t^3 - 41*t^2 - 41*t + 1)
%t A169488 coxG[{33,861,-41}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Aug 30 2016 *)
%K A169488 nonn
%O A169488 0,2
%A A169488 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009