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A164781
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Number of reduced words of length n in Coxeter group on 12 generators S_i with relations (S_i)^2 = (S_i S_j)^8 = I.
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0
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1, 12, 132, 1452, 15972, 175692, 1932612, 21258732, 233845986, 2572305120, 28295348400, 311248745280, 3423735239760, 37661077095840, 414271732097520, 4556987777548800, 50126851522277970, 551395212406754100
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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 A003954, 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)/(55*t^8 - 10*t^7 - 10*t^6 - 10*t^5 - 10*t^4 - 10*t^3 - 10*t^2 - 10*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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