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A164969
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Number of reduced words of length n in Coxeter group on 27 generators S_i with relations (S_i)^2 = (S_i S_j)^8 = I.
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0
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1, 27, 702, 18252, 474552, 12338352, 320797152, 8340725952, 216858874401, 5638330725300, 146596598620875, 3811511557982700, 99099300347388900, 2576581804867917600, 66991126818296818800, 1741769294460722280000
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OFFSET
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0,2
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COMMENTS
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The initial terms coincide with those of A170746, although the two sequences are eventually different.
Computed with MAGMA using commands similar to those used to compute A154638.
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LINKS
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FORMULA
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G.f. (t^8 + 2*t^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(325*t^8 -
25*t^7 - 25*t^6 - 25*t^5 - 25*t^4 - 25*t^3 - 25*t^2 - 25*t + 1)
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MATHEMATICA
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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