481572000
domain: N
Appears in sequences
- Numbers k for which sigma(k)/k - 4/7 is an integer.at n=12A218411
- Harmonic numbers m from A001599 such that m*(m-tau(m))/sigma(m) is an integer h, where k-tau(k) is the number of nondivisors of k (A049820), tau(k) is the number of divisors of k (A000005), and sigma(k) is the sum of the divisors of k (A000203).at n=20A325021