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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 (list; graph; refs; listen; history; text; internal format)
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.

LINKS

Table of n, a(n) for n=0..19.

FORMULA

G.f.: (t^3 + 2*t^2 + 2*t + 1)/(36*t^3 - 8*t^2 - 8*t + 1)

CROSSREFS

Sequence in context: A159733 A038726 A009454 * A199940 A004985 A164552

Adjacent sequences:  A162753 A162754 A162755 * A162757 A162758 A162759

KEYWORD

nonn

AUTHOR

John Cannon (john(AT)maths.usyd.edu.au) and N. J. A. Sloane, Dec 03 2009

STATUS

approved

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Last modified May 24 00:43 EDT 2013. Contains 225613 sequences.