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A164628
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Number of reduced words of length n in Coxeter group on 17 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
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0
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1, 17, 272, 4352, 69632, 1114112, 17825792, 285212536, 4563398400, 73014339720, 1168228880640, 18691653212160, 299066309345280, 4785058676736000, 76560902463178680, 1224973857577579200, 19599572411913213000
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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 A170736, 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)/(120*t^7 - 15*t^6 - 15*t^5 - 15*t^4 - 15*t^3 - 15*t^2 - 15*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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