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 A167916 #20 Nov 11 2023 08:50:17
%S A167916 1,12,132,1452,15972,175692,1932612,21258732,233846052,2572306572,
%T A167916 28295372292,311249095212,3423740047332,37661140520652,
%U A167916 414272545727172,4556998002998892,50126978032987746,551396758362864480
%N A167916 Number of reduced words of length n in Coxeter group on 12 generators S_i with relations (S_i)^2 = (S_i S_j)^16 = I.
%C A167916 The initial terms coincide with those of A003954, although the two sequences are eventually different.
%C A167916 Computed with MAGMA using commands similar to those used to compute A154638.
%H A167916 G. C. Greubel, <a href="/A167916/b167916.txt">Table of n, a(n) for n = 0..500</a>
%H A167916 <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,-55).
%F A167916 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)/( 55*t^16 - 10*t^15 - 10*t^14 - 10*t^13 - 10*t^12 - 10*t^11 - 10*t^10 - 10*t^9 - 10*t^8 - 10*t^7 - 10*t^6 - 10*t^5 - 10*t^4 - 10*t^3 - 10*t^2 - 10*t + 1).
%F A167916 From _G. C. Greubel_, Nov 10 2023: (Start)
%F A167916 a(n) = 10*Sum_{j=1..15} a(n-j) - 55*a(n-16).
%F A167916 G.f.: (1+x)*(1-x^16)/(1 - 11*x + 65*x^16 - 55*x^17). (End)
%t A167916 CoefficientList[Series[(1+t)*(1-t^16)/(1-11*t+65*t^16-55*t^17), {t,0,50}], t] (* _G. C. Greubel_, Jul 01 2016; Nov 10 2023 *)
%t A167916 coxG[{16,55,-10}] (* The coxG program is at A169452 *) (* _G. C. Greubel_, Nov 10 2023 *)
%o A167916 (Magma) R<x>:=PowerSeriesRing(Integers(), 30); Coefficients(R!( (1+x)*(1-x^16)/(1-11*x+65*x^16-55*x^17) )); // _G. C. Greubel_, Nov 10 2023
%o A167916 (SageMath)
%o A167916 def A167916_list(prec):
%o A167916 P.<x> = PowerSeriesRing(ZZ, prec)
%o A167916 return P( (1+x)*(1-x^16)/(1-11*x+65*x^16-55*x^17) ).list()
%o A167916 A167916_list(30) # _G. C. Greubel_, Nov 10 2023
%Y A167916 Cf. A003954, A154638, A169452.
%K A167916 nonn
%O A167916 0,2
%A A167916 _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009