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A168128
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Numbers Sum_(j=1..k) sigma(j) / sigma(k) when this expression is an integer.
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3
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1, 2, 23, 247, 699, 55921, 70936, 152730, 478017, 4879815, 12909834588, 223070292558, 583407686653, 601718433498
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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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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/s ", "))) \\ 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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