cp's OEIS Frontend

A170480 Number of reduced words of length n in Coxeter group on 39 generators S_i with relations (S_i)^2 = (S_i S_j)^45 = I.

%I A170480 #8 Nov 21 2016 17:03:58
%S A170480 1,39,1482,56316,2140008,81320304,3090171552,117426518976,
%T A170480 4462207721088,169563893401344,6443427949251072,244850262071540736,
%U A170480 9304309958718547968,353563778431304822784,13435423580389583265792
%N A170480 Number of reduced words of length n in Coxeter group on 39 generators S_i with relations (S_i)^2 = (S_i S_j)^45 = I.
%C A170480 The initial terms coincide with those of A170758, although the two sequences are eventually different.
%C A170480 Computed with MAGMA using commands similar to those used to compute A154638.
%H A170480 <a href="/index/Rec#order_45">Index entries for linear recurrences with constant coefficients</a>, signature (37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, -703).
%F A170480 G.f. (t^45 + 2*t^44 + 2*t^43 + 2*t^42 + 2*t^41 + 2*t^40 + 2*t^39 + 2*t^38 +
%F A170480 2*t^37 + 2*t^36 + 2*t^35 + 2*t^34 + 2*t^33 + 2*t^32 + 2*t^31 + 2*t^30 +
%F A170480 2*t^29 + 2*t^28 + 2*t^27 + 2*t^26 + 2*t^25 + 2*t^24 + 2*t^23 + 2*t^22 +
%F A170480 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*t^16 + 2*t^15 + 2*t^14 +
%F A170480 2*t^13 + 2*t^12 + 2*t^11 + 2*t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 +
%F A170480 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(703*t^45 - 37*t^44 - 37*t^43 -
%F A170480 37*t^42 - 37*t^41 - 37*t^40 - 37*t^39 - 37*t^38 - 37*t^37 - 37*t^36 -
%F A170480 37*t^35 - 37*t^34 - 37*t^33 - 37*t^32 - 37*t^31 - 37*t^30 - 37*t^29 -
%F A170480 37*t^28 - 37*t^27 - 37*t^26 - 37*t^25 - 37*t^24 - 37*t^23 - 37*t^22 -
%F A170480 37*t^21 - 37*t^20 - 37*t^19 - 37*t^18 - 37*t^17 - 37*t^16 - 37*t^15 -
%F A170480 37*t^14 - 37*t^13 - 37*t^12 - 37*t^11 - 37*t^10 - 37*t^9 - 37*t^8 -
%F A170480 37*t^7 - 37*t^6 - 37*t^5 - 37*t^4 - 37*t^3 - 37*t^2 - 37*t + 1)
%t A170480 coxG[{45,703,-37}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Feb 20 2016 *)
%K A170480 nonn
%O A170480 0,2
%A A170480 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009