cp's OEIS Frontend

A170036 Number of reduced words of length n in Coxeter group on 27 generators S_i with relations (S_i)^2 = (S_i S_j)^36 = I.

%I A170036 #6 Nov 26 2016 09:44:32
%S A170036 1,27,702,18252,474552,12338352,320797152,8340725952,216858874752,
%T A170036 5638330743552,146596599332352,3811511582641152,99099301148669952,
%U A170036 2576581829865418752,66991127576500887552,1741769316989023076352
%N A170036 Number of reduced words of length n in Coxeter group on 27 generators S_i with relations (S_i)^2 = (S_i S_j)^36 = I.
%C A170036 The initial terms coincide with those of A170746, although the two sequences are eventually different.
%C A170036 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170036 <a href="/index/Rec#order_36">Index entries for linear recurrences with constant coefficients</a>, signature (25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, -325).
%F A170036 G.f. (t^36 + 2*t^35 + 2*t^34 + 2*t^33 + 2*t^32 + 2*t^31 + 2*t^30 + 2*t^29 +
%F A170036 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 + 2*t^24 + 2*t^23 + 2*t^22 + 2*t^21 +
%F A170036 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*t^16 + 2*t^15 + 2*t^14 + 2*t^13 +
%F A170036 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4
%F A170036 + 2*t^3 + 2*t^2 + 2*t + 1)/(325*t^36 - 25*t^35 - 25*t^34 - 25*t^33 -
%F A170036 25*t^32 - 25*t^31 - 25*t^30 - 25*t^29 - 25*t^28 - 25*t^27 - 25*t^26 -
%F A170036 25*t^25 - 25*t^24 - 25*t^23 - 25*t^22 - 25*t^21 - 25*t^20 - 25*t^19 -
%F A170036 25*t^18 - 25*t^17 - 25*t^16 - 25*t^15 - 25*t^14 - 25*t^13 - 25*t^12 -
%F A170036 25*t^11 - 25*t^10 - 25*t^9 - 25*t^8 - 25*t^7 - 25*t^6 - 25*t^5 - 25*t^4
%F A170036 - 25*t^3 - 25*t^2 - 25*t + 1)
%K A170036 nonn
%O A170036 0,2
%A A170036 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009