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A048251
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a(n) is the smallest number whose sum of divisors is 6^n.
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14
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1, 5, 22, 102, 510, 3210, 17490, 112890, 600270, 3466470, 20205570, 118879530, 697118730, 3949737330, 24217298490, 143487592710, 841422307110, 4973562896610, 29520886859310, 180254162529210, 1052751138726210, 6301225298627490, 37854941354933010, 224270177470178070
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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sigma(k) = 1296 = 6^4 for each k in {510, 642, 710, 742, 782, 795, 862, 935, 1177, 1207, 1219}; the smallest of these is a(4)=510.
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PROG
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(PARI) a(n) = {my(k=1); while (sigma(k) != 6^n, k++); k; } \\ Michel Marcus, May 14 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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