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A164626
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Number of reduced words of length n in Coxeter group on 15 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
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0
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1, 15, 210, 2940, 41160, 576240, 8067360, 112942935, 1581199620, 22136774205, 309914552220, 4338799717980, 60743139868320, 850403171588880, 11905633390308840, 166678713297370365, 2333499827827833210
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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 A170734, 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)/(91*t^7 - 13*t^6 - 13*t^5 - 13*t^4 - 13*t^3 - 13*t^2 - 13*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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