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A165548
Number of reduced words of length n in Coxeter group on 32 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.
0
1, 32, 992, 30752, 953312, 29552672, 916132832, 28400117792, 880403651552, 27292513197616, 846067909110720, 26228105181956160, 813071260625880000, 25205209078944690240, 781361481433100114880, 24222205923986359801920
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A170751, although the two sequences are eventually different.
Computed with MAGMA using commands similar to those used to compute A154638.
FORMULA
G.f. (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)/(465*t^9 - 30*t^8 - 30*t^7 - 30*t^6 - 30*t^5 - 30*t^4 - 30*t^3 -
30*t^2 - 30*t + 1)
CROSSREFS
Sequence in context: A164036 A164668 A165131 * A166128 A166426 A166622
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved