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 A162831 #7 May 20 2018 16:53:28
%S A162831 1,29,812,22330,613872,16870518,463637790,12741680700,350166543426,
%T A162831 9623266966782,264466349471016,7268056690405518,199740527163222822,
%U A162831 5489263483947921132,150855782871027600954,4145814332316640869606
%N A162831 Number of reduced words of length n in Coxeter group on 29 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
%C A162831 The initial terms coincide with those of A170748, although the two sequences are eventually different.
%C A162831 Computed with MAGMA using commands similar to those used to compute A154638.
%H A162831 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (27, 27, -378).
%F A162831 G.f.: (t^3 + 2*t^2 + 2*t + 1)/(378*t^3 - 27*t^2 - 27*t + 1)
%t A162831 coxG[{3,378,-27}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, May 20 2018 *)
%K A162831 nonn
%O A162831 0,2
%A A162831 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009