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A164693
Number of reduced words of length n in Coxeter group on 48 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
0
1, 48, 2256, 106032, 4983504, 234224688, 11008560336, 517402334664, 24317909676192, 1142941752290400, 53718262240589472, 2524758319805916768, 118663640772294032544, 5577191104144368918624, 262127981323573161732216
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A170767, 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)/(1081*t^7 - 46*t^6 - 46*t^5 - 46*t^4 - 46*t^3 - 46*t^2 - 46*t + 1).
CROSSREFS
Sequence in context: A163266 A163829 A164348 * A165180 A165708 A166313
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved