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A163218 Number of reduced words of length n in Coxeter group on 35 generators S_i with relations (S_i)^2 = (S_i S_j)^4 = I. 0
1, 35, 1190, 40460, 1375045, 46731300, 1588176975, 53974651500, 1834344072330, 62340711467265, 2118667029023160, 72003509011079415, 2447059985777227590, 83164038200838759780, 2826353783752411211145, 96054447135432681999180 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The initial terms coincide with those of A170754, 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^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(561*t^4 - 33*t^3 - 33*t^2 - 33*t + 1)

CROSSREFS

Sequence in context: A046176 A162847 A029546 * A163600 A164068 A164671

Adjacent sequences:  A163215 A163216 A163217 * A163219 A163220 A163221

KEYWORD

nonn

AUTHOR

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

STATUS

approved

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Last modified December 19 07:59 EST 2014. Contains 252186 sequences.