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A181574
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a(n) = Product_{i=2..n} (tau(i)+1)/(tau(i)-1), where tau(.)=A000005(.).
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1
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1, 3, 9, 18, 54, 90, 270, 450, 900, 1500, 4500, 6300, 18900, 31500, 52500, 78750, 236250, 330750, 992250, 1389150, 2315250, 3858750, 11576250, 14883750, 29767500, 49612500, 82687500, 115762500, 347287500, 446512500, 1339537500, 1875352500, 3125587500
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OFFSET
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1,2
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COMMENTS
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The value of the empty product at n=1 is 1.
Partial products of the sequence of fractions 3, 3, 2, 3, 5/3, 3, 5/3, 2, 5/3, 3, 7/5, ...
The sequence is declared "fini" because the products are no longer integers at n >= 72.
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LINKS
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MAPLE
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A181574 := proc(n) mul( (numtheory[tau](i)+1)/(numtheory[tau](i)-1) , i=2..n) ; end proc; # R. J. Mathar, Feb 01 2011
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CROSSREFS
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KEYWORD
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nonn,easy,fini
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AUTHOR
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STATUS
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approved
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