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A166258 Number of reduced words of length n in Coxeter group on 45 generators S_i with relations (S_i)^2 = (S_i S_j)^10 = I. 0
1, 45, 1980, 87120, 3833280, 168664320, 7421230080, 326534123520, 14367501434880, 632170063134720, 27815482777926690, 1223881242228730800, 53850774658062239550, 2369434084954654251600, 104255099738001078372000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The initial terms coincide with those of A170764, 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.

FORMULA

G.f. (t^10 + 2*t^9 + 2*t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t

+ 1)/(946*t^10 - 43*t^9 - 43*t^8 - 43*t^7 - 43*t^6 - 43*t^5 - 43*t^4 -

43*t^3 - 43*t^2 - 43*t + 1)

CROSSREFS

Sequence in context: A164690 A165177 A165699 * A166439 A166738 A167098

Adjacent sequences:  A166255 A166256 A166257 * A166259 A166260 A166261

KEYWORD

nonn

AUTHOR

John Cannon (john(AT)maths.usyd.edu.au) and N. J. A. Sloane, Dec 03 2009

STATUS

approved

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Last modified May 22 09:01 EDT 2013. Contains 225516 sequences.