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A163958 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. 0

%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_ and _N. J. A. Sloane_, Dec 03 2009

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Last modified December 18 20:17 EST 2014. Contains 252174 sequences.