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A164637
Number of reduced words of length n in Coxeter group on 24 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
0
1, 24, 552, 12696, 292008, 6716184, 154472232, 3552861060, 81715798032, 1879463209008, 43227650455440, 994235883385008, 22867423544782608, 525950700749330736, 12096865179279290124, 278227877550453062232
OFFSET
0,2
COMMENTS
The initial terms coincide with those of A170743, although the two sequences are eventually different.
Computed with MAGMA using commands similar to those used to compute A154638.
FORMULA
G.f.: (t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(253*t^7 - 22*t^6 - 22*t^5 - 22*t^4 - 22*t^3 - 22*t^2 - 22*t + 1).
MATHEMATICA
coxG[{7, 253, -22}] (* The coxG program is at A169452 *) (* Harvey P. Dale, Jan 05 2022 *)
CROSSREFS
Sequence in context: A163174 A163519 A163992 * A164959 A165366 A165965
KEYWORD
nonn
AUTHOR
John Cannon and N. J. A. Sloane, Dec 03 2009
STATUS
approved