901170
domain: N
Appears in sequences
- Numbers k such that phi(k) = sigma(core(k)) where phi(k) is the Euler totient function, sigma(k) the sum of divisors of k and core(k) the squarefree part of k (the smallest integer such that k*core(k) is a square).at n=30A069552
- Ninth column (m=8) of (1,6)-Pascal triangle A096956.at n=14A097299
- Numbers n such that sigma(n) = 13*phi(n) (where sigma=A000203, phi=A000010).at n=22A171258