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A162767
Number of reduced words of length n in Coxeter group on 12 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
0
1, 12, 132, 1386, 14520, 151800, 1586970, 16589100, 173411700, 1812724650, 18948963000, 198079233000, 2070582104250, 21644420407500, 226255667302500, 2365118861366250, 24723302164275000, 258440148554775000
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A003954, although the two sequences are eventually different.
Computed with MAGMA using commands similar to those used to compute A154638.
FORMULA
G.f.: (t^3 + 2*t^2 + 2*t + 1)/(55*t^3 - 10*t^2 - 10*t + 1)
CROSSREFS
Sequence in context: A119237 A038729 A125447 * A003495 A324947 A165150
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved