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A162850 Number of reduced words of length n in Coxeter group on 36 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I. 0
1, 36, 1260, 43470, 1499400, 51707880, 1783182870, 61494142500, 2120662873980, 73132344752670, 2522013244518600, 86973155625205080, 2999321996442766470, 103433437289822465700, 3566964788136020871180, 123008943076595227404270 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The initial terms coincide with those of A170755, 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..15.

FORMULA

G.f.: (t^3 + 2*t^2 + 2*t + 1)/(595*t^3 - 34*t^2 - 34*t + 1)

CROSSREFS

Sequence in context: A001110 A064196 A060786 * A163219 A163601 A164069

Adjacent sequences:  A162847 A162848 A162849 * A162851 A162852 A162853

KEYWORD

nonn

AUTHOR

John Cannon and N. J. A. Sloane, Dec 03 2009

STATUS

approved

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Last modified August 29 19:56 EDT 2014. Contains 246211 sequences.