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A164639
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Number of reduced words of length n in Coxeter group on 26 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
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0
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1, 26, 650, 16250, 406250, 10156250, 253906250, 6347655925, 158691390000, 3967284547200, 99182108610000, 2479552588500000, 61988811543750000, 1549720209375000000, 38743003253906355300, 968575031835945300000
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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 A170745, 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^7 + 2*t^6 + 2*t^5 + 2*t^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(300*t^7 - 24*t^6 - 24*t^5 - 24*t^4 - 24*t^3 - 24*t^2 - 24*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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