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A306621
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Highly abundant numbers that are powerful.
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0
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1, 4, 8, 16, 36, 72, 108, 144, 216, 288, 1800, 3600, 7200
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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COMMENTS
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Alaoglu and Erdős proved that 7200 is the last term.
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LINKS
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MATHEMATICA
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seq={1}; sm = 0; Do[s = DivisorSigma[1, n]; If[s>sm, sm = s; If[ Min @ FactorInteger[n][[;; , 2]] > 1, AppendTo[seq, n]]], {n, 2, 72000}]; seq
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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