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A347064
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Smallest number with at least 2^n divisors.
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2
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1, 2, 6, 24, 120, 840, 7560, 83160, 1081080, 17297280, 294053760, 5587021440, 128501493120, 3212537328000, 93163582512000, 2888071057872000, 106858629141264000, 4381203794791824000, 184010559381256608000, 7912454053394034144000, 371885340509519604768000
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OFFSET
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0,2
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COMMENTS
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Begins to differ from A037992 at n=18; a(18) < A037992(18), but the number of divisors d(a(18)) = 276480 > 262144 = 2^18.
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LINKS
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FORMULA
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EXAMPLE
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-- ------------------------ ------------------------ ------- -------
18 188391763176048432000 184010559381256608000 276480 262144
19 8854412869274276304000 7912454053394034144000 552960 524288
20 433866230594439538896000 371885340509519604768000 1105920 1048576
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MATHEMATICA
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Table[SelectFirst[Table[{n, DivisorSigma[0, n]}, {n, 0, 11*10^5}], #[[2]]==2^k&], {k, 0, 8}][[;; , 1]] (* The program generates the first nine terms of the sequence. *) (* Harvey P. Dale, Feb 04 2024 *)
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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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