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A343220
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Number of unitary divisors d of n for which A003415(sigma(d)) > d.
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4
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0, 0, 1, 0, 0, 2, 1, 0, 0, 1, 1, 2, 0, 2, 2, 0, 1, 0, 1, 1, 3, 2, 1, 2, 0, 1, 1, 2, 1, 5, 1, 1, 3, 2, 2, 0, 0, 2, 2, 1, 0, 6, 1, 2, 1, 2, 1, 2, 0, 0, 3, 1, 1, 2, 2, 2, 3, 2, 1, 5, 0, 2, 2, 0, 1, 6, 1, 2, 3, 5, 1, 1, 0, 1, 2, 2, 3, 5, 1, 1, 0, 1, 1, 6, 2, 2, 3, 2, 1, 3, 2, 2, 3, 2, 2, 3, 0, 1, 2, 0, 0, 6, 1, 1, 6
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OFFSET
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1,6
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COMMENTS
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Number of divisors d of n such that gcd(d,n/d) = 1 and d is in A343218.
Number of terms k of A343218 that divide n, and k and n/k are relatively prime.
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LINKS
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FORMULA
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a(n) = Sum_{d|n, gcd(d,n/d)=1} A343219(d).
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PROG
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(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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