1476326929

Appears in sequences

• Squares whose sum of divisors is a square.at n=9A008848
• Duplicate of A008848.at n=9A074387
• Numbers n such that both sigma(n) and sigma(sigma(n)) are odd numbers.at n=16A097025
• Perfect (or pure) powers pp such that sigma(pp) is also a perfect (pure) power.at n=10A128607
• Odd numbers n such that b(n) >= n and b(b(n)) >= n, where b(n) = A161942(n) = oddpart(sigma(n)).at n=15A162284
• Sigma-powerful numbers: powerful numbers n such that sigma(n) is also powerful. An incomplete version of A337045.at n=19A180090
• Numbers n such that n, sigma(n) and sigma(sigma(n)) are odd.at n=2A231484