cp's OEIS Frontend

A170134 Number of reduced words of length n in Coxeter group on 29 generators S_i with relations (S_i)^2 = (S_i S_j)^38 = I.

%I A170134 #6 May 14 2017 17:36:30
%S A170134 1,29,812,22736,636608,17825024,499100672,13974818816,391294926848,
%T A170134 10956257951744,306775222648832,8589706234167296,240511774556684288,
%U A170134 6734329687587160064,188561231252440481792,5279714475068333490176
%N A170134 Number of reduced words of length n in Coxeter group on 29 generators S_i with relations (S_i)^2 = (S_i S_j)^38 = I.
%C A170134 The initial terms coincide with those of A170748, although the two sequences are eventually different.
%C A170134 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170134 <a href="/index/Rec#order_38">Index entries for linear recurrences with constant coefficients</a>, signature (27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, -378).
%F A170134 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 A170134 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 A170134 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 A170134 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 A170134 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(378*t^38 - 27*t^37 -
%F A170134 27*t^36 - 27*t^35 - 27*t^34 - 27*t^33 - 27*t^32 - 27*t^31 - 27*t^30 -
%F A170134 27*t^29 - 27*t^28 - 27*t^27 - 27*t^26 - 27*t^25 - 27*t^24 - 27*t^23 -
%F A170134 27*t^22 - 27*t^21 - 27*t^20 - 27*t^19 - 27*t^18 - 27*t^17 - 27*t^16 -
%F A170134 27*t^15 - 27*t^14 - 27*t^13 - 27*t^12 - 27*t^11 - 27*t^10 - 27*t^9 -
%F A170134 27*t^8 - 27*t^7 - 27*t^6 - 27*t^5 - 27*t^4 - 27*t^3 - 27*t^2 - 27*t + 1)
%K A170134 nonn
%O A170134 0,2
%A A170134 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009