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A168130
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Numbers Sum_(j=1..k) sigma(j) when Sum_(j=1..k) sigma(j) / sigma(k) is an integer.
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3
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1, 8, 690, 109668, 1235133, 5475784320, 6118230000, 28361961000, 279467858880, 107135567314230, 227917248343616414016, 79758963630439261338240, 413838290195487519174516, 638755027963568013738240
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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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EXAMPLE
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PROG
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(PARI) m=0; for(k=1, 11413204, s=sigma(k); m=m+s; if(m%s==0, print1(m ", "))) \\ Donovan Johnson, Oct 16 2013
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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