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A162756
Number of reduced words of length n in Coxeter group on 10 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
0
1, 10, 90, 765, 6480, 54720, 462060, 3900960, 32934240, 278047440, 2347418880, 19818097920, 167314426560, 1412553116160, 11925488816640, 100681016106240, 850000127201280, 7176131549061120, 60584536830274560, 511485342455439360
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A003952, 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)/(36*t^3 - 8*t^2 - 8*t + 1)
CROSSREFS
Sequence in context: A231530 A242652 A291392 * A331323 A199940 A004985
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved