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 A165321 #8 Jan 31 2021 12:53:11
%S A165321 1,17,272,4352,69632,1114112,17825792,285212672,4563402752,
%T A165321 73014443896,1168231100160,18691697567880,299067160531200,
%U A165321 4785074559621120,76561192811888640,1224979082717429760,19599665287114260480
%N A165321 Number of reduced words of length n in Coxeter group on 17 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.
%C A165321 The initial terms coincide with those of A170736, although the two sequences are eventually different.
%C A165321 Computed with MAGMA using commands similar to those used to compute A154638.
%H A165321 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (15, 15, 15, 15, 15, 15, 15, 15, -120).
%F A165321 G.f. (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 +
%F A165321 1)/(120*t^9 - 15*t^8 - 15*t^7 - 15*t^6 - 15*t^5 - 15*t^4 - 15*t^3 -
%F A165321 15*t^2 - 15*t + 1)
%t A165321 coxG[{9,120,-15}] (* The coxG program is at A169452 *) (* _Harvey P. Dale_, Jan 31 2021 *)
%K A165321 nonn
%O A165321 0,2
%A A165321 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009