4358600
domain: N
Appears in sequences
- Numbers n such that harmonic mean of the divisors of n is a prime.at n=14A074247
- a(n) = smallest number m such that m*tau(m)/sigma(m) = n, or 0 if no such m exists.at n=36A091911
- Harmonic numbers that are not multiply-perfect.at n=30A140798
- Harmonic numbers m from A001599 such that m*(m-tau(m))/sigma(m) is not an integer, where k-tau(k) = the number of nondivisors of k (A049820), tau(k) = the number of divisors of k (A000005) and sigma(k) = the sum of the divisors of k (A000203).at n=28A325022