cp's OEIS Frontend

A169475 Number of reduced words of length n in Coxeter group on 30 generators S_i with relations (S_i)^2 = (S_i S_j)^33 = I.

%I A169475 #6 Nov 26 2016 07:23:52
%S A169475 1,30,870,25230,731670,21218430,615334470,17844699630,517496289270,
%T A169475 15007392388830,435214379276070,12621216999006030,366015292971174870,
%U A169475 10614443496164071230,307818861388758065670,8926746980273983904430
%N A169475 Number of reduced words of length n in Coxeter group on 30 generators S_i with relations (S_i)^2 = (S_i S_j)^33 = I.
%C A169475 The initial terms coincide with those of A170749, although the two sequences are eventually different.
%C A169475 Computed with MAGMA using commands similar to those used to compute A154638.
%H A169475 <a href="/index/Rec#order_33">Index entries for linear recurrences with constant coefficients</a>, signature (28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, -406).
%F A169475 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 A169475 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 A169475 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 A169475 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 A169475 1)/(406*t^33 - 28*t^32 - 28*t^31 - 28*t^30 - 28*t^29 - 28*t^28 - 28*t^27
%F A169475 - 28*t^26 - 28*t^25 - 28*t^24 - 28*t^23 - 28*t^22 - 28*t^21 - 28*t^20 -
%F A169475 28*t^19 - 28*t^18 - 28*t^17 - 28*t^16 - 28*t^15 - 28*t^14 - 28*t^13 -
%F A169475 28*t^12 - 28*t^11 - 28*t^10 - 28*t^9 - 28*t^8 - 28*t^7 - 28*t^6 - 28*t^5
%F A169475 - 28*t^4 - 28*t^3 - 28*t^2 - 28*t + 1)
%K A169475 nonn
%O A169475 0,2
%A A169475 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009