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A168129
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Numbers sigma(k) when Sum_(j=1..k) sigma(j) / sigma(k) is an integer.
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3
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1, 4, 30, 444, 1767, 86250, 97920, 185700, 584640, 21954842, 17654544432, 357550809280, 709346653572, 1061551370880
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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) v=vector(10); c=0; m=0; for(k=1, 11413204, s=sigma(k); m=m+s; if(m%s==0, c++; v[c]=s)); v=vecsort(v); for(i=1, c, print1(v[i] ", ")) \\ 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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