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 A166611 #11 Mar 17 2020 14:41:46
%S A166611 1,24,552,12696,292008,6716184,154472232,3552861336,81715810728,
%T A166611 1879463646744,43227663875112,994236269127576,22867434189933972,
%U A166611 525950986368475008,12096872686474779456,278228071788916575744
%N A166611 Number of reduced words of length n in Coxeter group on 24 generators S_i with relations (S_i)^2 = (S_i S_j)^12 = I.
%C A166611 The initial terms coincide with those of A170743, although the two sequences are eventually different.
%C A166611 Computed with MAGMA using commands similar to those used to compute A154638.
%H A166611 G. C. Greubel, <a href="/A166611/b166611.txt">Table of n, a(n) for n = 0..500</a>
%H A166611 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, -253).
%F A166611 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)/(253*t^12 - 22*t^11 - 22*t^10 - 22*t^9 -22*t^8 -22*t^7 - 22*t^6 - 22*t^5 - 22*t^4 - 22*t^3 - 22*t^2 -22*t + 1).
%t A166611 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)/(253*t^12 - 22*t^11 - 22*t^10 - 22*t^9 - 22*t^8 - 22*t^7 - 22*t^6 - 22*t^5 - 22*t^4 - 22*t^3 - 22*t^2 - 22*t + 1), {t, 0, 50}], t] (* _G. C. Greubel_, May 18 2016 *)
%t A166611 coxG[{12,253,-22}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Mar 17 2020 *)
%K A166611 nonn
%O A166611 0,2
%A A166611 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009