355744082763
domain: N
Appears in sequences
- Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (2,4)-perfect numbers.at n=3A019282
- Odd terms of A019278: odd n such that sigma(sigma(n))/n is an integer.at n=6A205597
- Subsequence of terms of A019278 whose sum of divisors is also a term of A019278.at n=32A292949
- Integers m such that m and sigma(m) are relatively prime and sigma(sigma(m))/m is an integer.at n=13A328265