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A165651
Number of reduced words of length n in Coxeter group on 36 generators S_i with relations (S_i)^2 = (S_i S_j)^9 = I.
0
1, 36, 1260, 44100, 1543500, 54022500, 1890787500, 66177562500, 2316214687500, 81067514061870, 2837362992143400, 99307704724247880, 3475769665321686600, 121651938285314409000, 4257817839952942545000, 149023624397195827125000
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A170755, 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)/(595*t^9 - 34*t^8 - 34*t^7 - 34*t^6 - 34*t^5 - 34*t^4 - 34*t^3 -
34*t^2 - 34*t + 1)
MATHEMATICA
coxG[{9, 595, -34}] (* The coxG program is at A169452 *) (* Harvey P. Dale, Oct 05 2023 *)
CROSSREFS
Sequence in context: A164069 A164672 A165168 * A166165 A166430 A166688
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved