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%I
%S 1,13,156,1872,22464,269568,3234738,38815920,465779886,5589224784,
%T 67069091232,804809820672,9657486564726,115887063443580,
%U 1390611458122458,16686937868633604,200238458992414128
%N Number of reduced words of length n in Coxeter group on 13 generators S_i with relations (S_i)^2 = (S_i S_j)^6 = I.
%C The initial terms coincide with those of A170732, although the two sequences are eventually different.
%C Computed with MAGMA using commands similar to those used to compute A154638.
%F G.f. (t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(66*t^6 - 11*t^5 - 11*t^4 -
%F 11*t^3 - 11*t^2 - 11*t + 1)
%K nonn
%O 0,2
%A John Cannon (john(AT)maths.usyd.edu.au) and _N. J. A. Sloane_, Dec 03 2009
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