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A165703
Number of reduced words of length n in Coxeter group on 47 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.
0
1, 47, 2162, 99452, 4574792, 210440432, 9680259872, 445291954112, 20483429889152, 942237774899911, 43342937645346180, 1993775131683637965, 91713656057342175900, 4218828178632902248860, 194066096216890962690720
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A170766, although the two sequences are eventually different.
Computed with MAGMA using commands similar to those used to compute A154638.
FORMULA
G.f. (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)/(1035*t^9 - 45*t^8 - 45*t^7 - 45*t^6 - 45*t^5 - 45*t^4 - 45*t^3 -
45*t^2 - 45*t + 1)
MATHEMATICA
coxG[{9, 1035, -45}] (* The coxG program is at A169452 *) (* Harvey P. Dale, Feb 25 2015 *)
CROSSREFS
Sequence in context: A164332 A164692 A165179 * A166308 A166441 A166740
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved