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A162811 Number of reduced words of length n in Coxeter group on 25 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I. 0
1, 25, 600, 14100, 331200, 7776300, 182580900, 4286804400, 100649603100, 2363145044100, 55484118871200, 1302707779596300, 30586185632580900, 718130931671624400, 16860946350828143100, 395876990262902324100 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The initial terms coincide with those of A170744, 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.

Index entries for linear recurrences with constant coefficients, signature (23, 23, -276).

FORMULA

G.f.: (t^3 + 2*t^2 + 2*t + 1)/(276*t^3 - 23*t^2 - 23*t + 1)

CROSSREFS

Sequence in context: A228827 A159661 A104643 * A163175 A163525 A163993

Adjacent sequences:  A162808 A162809 A162810 * A162812 A162813 A162814

KEYWORD

nonn

AUTHOR

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

STATUS

approved

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Last modified September 15 08:31 EDT 2019. Contains 327062 sequences. (Running on oeis4.)