223938

Appears in sequences

• a(n) = (n + 1)*(n + 2)*(n + 4)*(n + 8)*(n + 15)/120.at n=25A006636
• 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=19A069552
• Numbers n such that sigma(n) = 10*phi(n) (where sigma=A000203, phi=A000010).at n=21A171256
• Numbers k such that sigma(k) = psi(k) + phi(k).at n=28A389478