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A335010
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a(n) = Product_{k=1..n} (2^k - 1)^k.
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1
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1, 9, 3087, 156279375, 4474145825060625, 279739266376566114746420625, 149066302192479440045478394157489352699375, 2665022756273454714861436593121414601862237540654765380859375
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) ~ c * 2^(n*(n+1)*(2*n+1)/6), where c = A335011 = Product_{k>=1} (1 - 1/2^k)^k.
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MATHEMATICA
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Table[Product[(2^k - 1)^k, {k, 1, n}], {n, 1, 10}]
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PROG
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(PARI) a(n) = prod(k=1, n, (2^k-1)^k); \\ Michel Marcus, May 19 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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