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A162808
Number of reduced words of length n in Coxeter group on 22 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
0
1, 22, 462, 9471, 194040, 3973200, 81355890, 1665833400, 34109413800, 698420207100, 14300767404000, 292820775324000, 5995762611069000, 122768506573020000, 2513793020863740000, 51472120400410710000
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A170741, 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)/(210*t^3 - 20*t^2 - 20*t + 1)
MATHEMATICA
coxG[{3, 210, -20}] (* The coxG program is at A169452 *) (* Harvey P. Dale, Mar 09 2018 *)
CROSSREFS
Sequence in context: A231659 A269681 A269470 * A212335 A342887 A163149
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved