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A163175
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Number of reduced words of length n in Coxeter group on 25 generators S_i with relations (S_i)^2 = (S_i S_j)^4 = I.
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0
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1, 25, 600, 14400, 345300, 8280000, 198547500, 4761000000, 114164729700, 2737573095600, 65644673871900, 1574103433035600, 37745661174674100, 905108843301991200, 21703740051934476300, 520437222249938431200
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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 A170744, 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)/(276*t^4 - 23*t^3 - 23*t^2 - 23*t + 1).
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MATHEMATICA
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CoefficientList[Series[(t^4 + 2 t^3 + 2 t^2 + 2 t + 1)/(276 t^4 - 23 t^3 - 23 t^2 - 23 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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