This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A166616 #9 Nov 24 2016 09:41:46
%S A166616 1,29,812,22736,636608,17825024,499100672,13974818816,391294926848,
%T A166616 10956257951744,306775222648832,8589706234167296,240511774556683882,
%U A166616 6734329687587137328,188561231252439527286,5279714475068297862864
%N A166616 Number of reduced words of length n in Coxeter group on 29 generators S_i with relations (S_i)^2 = (S_i S_j)^12 = I.
%C A166616 The initial terms coincide with those of A170748, although the two sequences are eventually different.
%C A166616 Computed with MAGMA using commands similar to those used to compute A154638.
%H A166616 G. C. Greubel, <a href="/A166616/b166616.txt">Table of n, a(n) for n = 0..500</a>
%H A166616 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, -378).
%F A166616 G.f.: (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 + 2*t^3 + 2*t^2 + 2*t + 1)/(378*t^12 - 27*t^11 - 27*t^10 - 27*t^9 -27*t^8 -27*t^7 - 27*t^6 - 27*t^5 - 27*t^4 - 27*t^3 - 27*t^2 - 27*t +1).
%t A166616 CoefficientList[Series[(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 + 2*t^3 + 2*t^2 + 2*t + 1)/(378*t^12 - 27*t^11 - 27*t^10 - 27*t^9 - 27*t^8 - 27*t^7 - 27*t^6 - 27*t^5 - 27*t^4 - 27*t^3 - 27*t^2 - 27*t + 1), {t, 0, 50}], t] (* _G. C. Greubel_, May 19 2016 *)
%K A166616 nonn
%O A166616 0,2
%A A166616 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009