A162919 Number of reduced words of length n in Coxeter group on 50 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.

1, 50, 2450, 118825, 5762400, 279417600, 13548901800, 656982748800, 31856924131200, 1544734021723200, 74903753688422400, 3632063667308697600, 176117828998315276800, 8539908033612366028800, 414097934532557674291200

Offset

0,2

Comments

The initial terms coincide with those of A170769, 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..14.

Index entries for linear recurrences with constant coefficients, signature (48, 48, -1176).

Formula

G.f.: (t^3 + 2*t^2 + 2*t + 1)/(1176*t^3 - 48*t^2 - 48*t + 1)

Crossrefs

Sequence in context: A231696 A285877 A156087 * A163290 A163837 A164351

Adjacent sequences: A162916 A162917 A162918 * A162920 A162921 A162922

Keyword

nonn

Author

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

Status

approved