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A164636
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Number of reduced words of length n in Coxeter group on 23 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.
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0
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1, 23, 506, 11132, 244904, 5387888, 118533536, 2607737539, 57370220292, 1262144724225, 27767181244572, 610877928236268, 13439313120022944, 295664860014655824, 6504626290553815116, 143101764537275790477
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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 A170742, 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)/(231*t^7 - 21*t^6 - 21*t^5 - 21*t^4 - 21*t^3 - 21*t^2 - 21*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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