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A345160
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a(n) = Product_{k=1..n} sigma_3(k).
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3
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1, 9, 252, 18396, 2317896, 584109792, 200933768448, 117546254542080, 88982514688354560, 100906171656594071040, 134407020646583302625280, 274727950201616270566072320, 603852034543152562704226959360, 1869525898945600334132286666178560
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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Lim_{n->infinity} (a(n) / (n!)^3)^(1/n) = A345159.
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MATHEMATICA
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Table[Product[DivisorSigma[3, k], {k, 1, n}], {n, 1, 20}]
FoldList[Times, DivisorSigma[3, Range[20]]] (* Harvey P. Dale, Sep 18 2023 *)
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PROG
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(PARI) a(n) = prod(k=1, n, sigma(k, 3)); \\ Michel Marcus, Jun 10 2021
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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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