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 A167109 #12 Nov 24 2016 10:43:41 %S A167109 1,8,56,392,2744,19208,134456,941192,6588344,46118408,322828856, %T A167109 2259801992,15818613944,110730297608,775112083228,5425784582400, %U A167109 37980492075456,265863444518784,1861044111565632,13027308780498432 %N A167109 Number of reduced words of length n in Coxeter group on 8 generators S_i with relations (S_i)^2 = (S_i S_j)^14 = I. %C A167109 The initial terms coincide with those of A003950, although the two sequences are eventually different. %C A167109 Computed with MAGMA using commands similar to those used to compute A154638. %H A167109 G. C. Greubel, <a href="/A167109/b167109.txt">Table of n, a(n) for n = 0..500</a> %H A167109 <a href="/index/Rec#order_14">Index entries for linear recurrences with constant coefficients</a>, signature (6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, -21). %F A167109 G.f.: (t^14 + 2*t^13 + 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 + 2*t^3 + 2*t^2 + 2*t + 1)/(21*t^14 - 6*t^13 - 6*t^12 - 6*t^11 - 6*t^10 - 6*t^9 - 6*t^8 - 6*t^7 - 6*t^6 - 6*t^5 - 6*t^4 - 6*t^3 - 6*t^2 - 6*t + 1). %t A167109 With[{num=Total[2t^Range[13]]+t^14+1,den=Total[-6 t^Range[13]]+ 21t^14+1}, CoefficientList[Series[num/den,{t,0,30}],t]] (* _Harvey P. Dale_, Jul 15 2011 *) %t A167109 CoefficientList[Series[(t^14 + 2*t^13 + 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 + 2*t^3 + 2*t^2 + 2*t + 1)/ (21*t^14 - 6*t^13 - 6*t^12 - 6*t^11 - 6*t^10 - 6*t^9 - 6*t^8 - 6*t^7 - 6*t^6 - 6*t^5 - 6*t^4 - 6*t^3 - 6*t^2 - 6*t + 1), {t, 0, 50}], t] (* _G. C. Greubel_, Jun 03 2016 *) %K A167109 nonn %O A167109 0,2 %A A167109 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009