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A162791
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Number of reduced words of length n in Coxeter group on 16 generators S_i with relations (S_i)^2 = (S_i S_j)^3 = I.
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0
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1, 16, 240, 3480, 50400, 729120, 10547880, 152586000, 2207316720, 31931110680, 461916453600, 6682097644320, 96663430749480, 1398336169885200, 20228374156231920, 292624284336944280, 4233111921066520800
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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 A170735, 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^3 + 2*t^2 + 2*t + 1)/(105*t^3 - 14*t^2 - 14*t + 1)
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MATHEMATICA
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CoefficientList[Series[(t^3+2t^2+2t+1)/(105t^3-14t^2-14t+1), {t, 0, 30}], t] (* Harvey P. Dale, Oct 02 2011 *)
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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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