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A066924
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Nonprime numbers n such that the GCD of n and the Chowla's function of n (A048050) is >= n/3.
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0
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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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MATHEMATICA
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Select[ Range[ 10^7 ], GCD[ #, DivisorSigma[ 1, # ] - # - 1 ] >= #/3 && !PrimeQ[ # ] & ]
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PROG
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(PARI) f(n) = if(n>1, sigma(n)-n-1, 0); \\ A048050
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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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