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 A167898 #10 Nov 24 2016 12:34:18
%S A167898 1,7,42,252,1512,9072,54432,326592,1959552,11757312,70543872,
%T A167898 423263232,2539579392,15237476352,91424858112,548549148672,
%U A167898 3291294892011,19747769351940,118486616110905,710919696661020,4265518179939660
%N A167898 Number of reduced words of length n in Coxeter group on 7 generators S_i with relations (S_i)^2 = (S_i S_j)^16 = I.
%C A167898 The initial terms coincide with those of A003949, although the two sequences are eventually different.
%C A167898 Computed with MAGMA using commands similar to those used to compute A154638.
%H A167898 G. C. Greubel, <a href="/A167898/b167898.txt">Table of n, a(n) for n = 0..500</a>
%H A167898 <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, -15).
%F A167898 G.f.: (t^16 + 2*t^15 + 2*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)/( 15*t^16 - 5*t^15 - 5*t^14 - 5*t^13 - 5*t^12 - 5*t^11 - 5*t^10 - 5*t^9 - 5*t^8 - 5*t^7 - 5*t^6 - 5*t^5 - 5*t^4 - 5*t^3 - 5*t^2 - 5*t + 1).
%t A167898 CoefficientList[Series[(t^16 + 2*t^15 + 2*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)/(15*t^16 - 5*t^15 - 5*t^14 - 5*t^13 - 5*t^12 - 5*t^11 - 5*t^10 - 5*t^9 - 5*t^8 - 5*t^7 - 5*t^6 - 5*t^5 - 5*t^4 - 5*t^3 - 5*t^2 - 5*t + 1), {t, 0, 50}], t] (* _G. C. Greubel_, Jul 01 2016 *)
%K A167898 nonn
%O A167898 0,2
%A A167898 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009