66571993057
domain: N
Appears in sequences
- a(n) = A000043(n) * A000668(n).at n=7A131960
- Semiprimes that are a product of distinct Mersenne primes.at n=22A144856
- Numbers n with the property that there are integers k, h such that sigma(n) = k^tau(n) = tau(n)^h.at n=13A225362
- a(1) = 1; for n > 1, a(n) is the smallest number m such that sigma(m) = tau(m)^n or 0 if no such m exists.at n=17A349006