%I #11 Nov 25 2016 12:24:44
%S 1,44,1892,81356,3498308,150427244,6468371492,278139974156,
%T 11960018888708,514280812214444,22114074925221092,950905221784506956,
%U 40888924536733799108,1758223755079553361644,75603621468420794550692
%N Number of reduced words of length n in Coxeter group on 44 generators S_i with relations (S_i)^2 = (S_i S_j)^26 = I.
%C The initial terms coincide with those of A170763, although the two sequences are eventually different.
%C First disagreement at index 26: a(26) = 3021092800814089671710786088248205117418546, A170763(26) = 3021092800814089671710786088248205117419492. - Klaus Brockhaus, Apr 30 2011
%C Computed with MAGMA using commands similar to those used to compute A154638.
%H <a href="/index/Rec#order_26">Index entries for linear recurrences with constant coefficients</a>, signature (42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, -903).
%F G.f.: (t^26 + 2*t^25 + 2*t^24 + 2*t^23 + 2*t^22 + 2*t^21 + 2*t^20 + 2*t^19 + 2*t^18 + 2*t^17 + 2*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)/(903*t^26 - 42*t^25 - 42*t^24 - 42*t^23 - 42*t^22 - 42*t^21 - 42*t^20 - 42*t^19 - 42*t^18 - 42*t^17 - 42*t^16 - 42*t^15 - 42*t^14 - 42*t^13 - 42*t^12 - 42*t^11 - 42*t^10 - 42*t^9 - 42*t^8 - 42*t^7 - 42*t^6 - 42*t^5 - 42*t^4 - 42*t^3 - 42*t^2 - 42*t + 1).
%t With[{num=Total[2t^Range[25]]+t^26+1,den=Total[-42 t^Range[25]]+ 903t^26+1}, CoefficientList[Series[num/den,{t,0,30}],t]] (* _Harvey P. Dale_, Feb 05 2012 *)
%Y Cf. A170763 (G.f.: (1+x)/(1-43*x)).
%K nonn
%O 0,2
%A _John Cannon_ and _N. J. A. Sloane_, Dec 03 2009
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