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A163174
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Number of reduced words of length n in Coxeter group on 24 generators S_i with relations (S_i)^2 = (S_i S_j)^4 = I.
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0
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1, 24, 552, 12696, 291732, 6703488, 154034496, 3539441664, 81330144060, 1868823662376, 42942280730712, 986738081076264, 22673505553878564, 520997277758500752, 11971601073631152624, 275086336118245407888
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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 A170743, 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^4 + 2*t^3 + 2*t^2 + 2*t + 1)/(253*t^4 - 22*t^3 - 22*t^2 - 22*t + 1).
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MATHEMATICA
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CoefficientList[Series[(t^4 + 2 t^3 + 2 t^2 + 2 t + 1)/(253 t^4 - 22 t^3 - 22 t^2 - 22 t + 1), {t, 0, 20}], t] (* Jinyuan Wang, Mar 23 2020 *)
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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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