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A162833 Number of reduced words of length n in Coxeter group on 30 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I. 0
1, 30, 870, 24795, 706440, 20121360, 573111630, 16323709080, 464941707720, 13242748348620, 377187895691040, 10743291699776160, 305996872843541880, 8715586321562342880, 248242553013255652320, 7070593171000425862320 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The initial terms coincide with those of A170749, 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 (28, 28, -406).

FORMULA

G.f.: (t^3 + 2*t^2 + 2*t + 1)/(406*t^3 - 28*t^2 - 28*t + 1)

CROSSREFS

Sequence in context: A256324 A001201 A007850 * A163208 A163552 A164027

Adjacent sequences:  A162830 A162831 A162832 * A162834 A162835 A162836

KEYWORD

nonn

AUTHOR

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

STATUS

approved

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Last modified November 21 01:23 EST 2019. Contains 329348 sequences. (Running on oeis4.)