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 A343220 Number of unitary divisors d of n for which A003415(sigma(d)) > d. 3
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 COMMENTS 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. LINKS Antti Karttunen, Table of n, a(n) for n = 1..65537 FORMULA a(n) = Sum_{d|n, gcd(d,n/d)=1} A343219(d). PROG (PARI) A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1])); A343219(n) = (A003415(sigma(n))>n); A343220(n) = sumdiv(n, d, if(1==gcd(d, n/d), A343219(d), 0)); CROSSREFS Cf. A000203, A003415, A342925, A343218, A343219, A343225 (positions of 1's). Sequence in context: A335664 A269518 A219840 * A264893 A340653 A334744 Adjacent sequences:  A343217 A343218 A343219 * A343221 A343222 A343223 KEYWORD nonn,look AUTHOR Antti Karttunen, Apr 09 2021 STATUS approved

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Last modified June 17 00:17 EDT 2021. Contains 345080 sequences. (Running on oeis4.)