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 A164686 #10 Feb 22 2024 17:47:46 %S A164686 1,42,1722,70602,2894682,118681962,4865960442,199504377261, %T A164686 8179679432400,335366855281920,13750041007253040,563751678865841760, %U A164686 23113818733806664080,947666563998666456000,38854328956361647813980 %N A164686 Number of reduced words of length n in Coxeter group on 42 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I. %C A164686 The initial terms coincide with those of A170761, although the two sequences are eventually different. %C A164686 Computed with MAGMA using commands similar to those used to compute A154638. %H A164686 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (40,40,40,40,40,40,-820). %F A164686 G.f.: (t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(820*t^7 - 40*t^6 - 40*t^5 - 40*t^4 - 40*t^3 - 40*t^2 - 40*t + 1). %K A164686 nonn %O A164686 0,2 %A A164686 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009