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A164769
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Number of reduced words of length n in Coxeter group on 8 generators S_i with relations (S_i)^2 = (S_i S_j)^8 = I.
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0
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1, 8, 56, 392, 2744, 19208, 134456, 941192, 6588316, 46118016, 322824768, 2259763968, 15818281920, 110727512448, 775089360192, 5425602932736, 37979062409652, 265852330035768, 1860958562459976, 13026655702912824
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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 A003950, 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)/(21*t^8 - 6*t^7 - 6*t^6 - 6*t^5 - 6*t^4 - 6*t^3 - 6*t^2 - 6*t + 1).
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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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