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A164692
Number of reduced words of length n in Coxeter group on 47 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
0
1, 47, 2162, 99452, 4574792, 210440432, 9680259872, 445291953031, 20483429789700, 942237768039885, 43342937224664220, 1993775107496711580, 91713654722307975840, 4218828106989292074000, 194066092450611195098040
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^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(1035*t^7 - 45*t^6 - 45*t^5 - 45*t^4 - 45*t^3 - 45*t^2 - 45*t + 1).
CROSSREFS
Sequence in context: A163265 A163803 A164332 * A165179 A165703 A166308
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved