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 A165876 #17 Sep 08 2022 08:45:48
%S A165876 1,16,240,3600,54000,810000,12150000,182250000,2733750000,41006250000,
%T A165876 615093749880,9226406246400,138396093669120,2075941404633600,
%U A165876 31139121063456000,467086815861120000,7006302236556000000
%N A165876 Number of reduced words of length n in Coxeter group on 16 generators S_i with relations (S_i)^2 = (S_i S_j)^10 = I.
%C A165876 The initial terms coincide with those of A170735, although the two sequences are eventually different.
%C A165876 Computed with MAGMA using commands similar to those used to compute A154638.
%H A165876 G. C. Greubel, <a href="/A165876/b165876.txt">Table of n, a(n) for n = 0..500</a>
%H A165876 <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (14,14,14,14,14,14,14,14,14,-105).
%F A165876 G.f.: (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)/(105*t^10 - 14*t^9 - 14*t^8 - 14*t^7 - 14*t^6 - 14*t^5 - 14*t^4 - 14*t^3 - 14*t^2 - 14*t + 1).
%p A165876 seq(coeff(series((1+t)*(1-t^10)/(1-15*t+129*t^10-105*t^11), t, n+1), t, n), n = 0..20); # _G. C. Greubel_, Sep 23 2019
%t A165876 CoefficientList[Series[(1+t)*(1-t^10)/(1-15*t+129*t^10-105*t^11), {t, 0, 25}], t] (* _G. C. Greubel_, Apr 17 2016 *)
%t A165876 coxG[{10, 105, -14}] (* The coxG program is at A169452 *) (* _G. C. Greubel_, Aug 10 2019 *)
%o A165876 (PARI) my(t='t+O('t^20)); Vec((1+t)*(1-t^10)/(1-15*t+129*t^10-105*t^11)) \\ _G. C. Greubel_, Aug 07 2017
%o A165876 (Magma) R<t>:=PowerSeriesRing(Integers(), 20); Coefficients(R!( (1+t)*(1-t^10)/(1-15*t+129*t^10-105*t^11) )); // _G. C. Greubel_, Aug 10 2019
%o A165876 (Sage)
%o A165876 def A165876_list(prec):
%o A165876 P.<t> = PowerSeriesRing(ZZ, prec)
%o A165876 return P((1+t)*(1-t^10)/(1-15*t+129*t^10-105*t^11)).list()
%o A165876 A165876_list(20) # _G. C. Greubel_, Aug 10 2019
%o A165876 (GAP) a:=[16, 240, 3600, 54000, 810000, 12150000, 182250000, 2733750000, 41006250000, 615093749880];; for n in [11..20] do a[n]:=14*Sum([1..9], j-> a[n-j]) -105*a[n-10]; od; Concatenation([1], a); # _G. C. Greubel_, Aug 10 2019
%Y A165876 Cf. A154638, A170735.
%K A165876 nonn
%O A165876 0,2
%A A165876 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009