2165407

Appears in sequences

• Numbers k > 1 such that sigma(phi(k))/sigma(k) > sigma(phi(j))/sigma(j) for all 1 < j < k.at n=29A067573
• Numbers k such that sigma(phi(k))/k > sigma(phi(m))/m for all m < k, where sigma is the sum of divisors function (A000203) and phi is Euler's totient function (A000010).at n=31A293059
• The smallest number such that n or more numbers k exist such that a(n) - k = sopfr(a(n)) + sopfr(k), where sopfr(m) is the sum of the primes dividing m, with repetition.at n=24A369351
• The smallest number such that exactly n numbers k exist such that a(n) - k = sopfr(a(n)) + sopfr(k), where sopfr(m) is the sum of the primes dividing m, with repetition.at n=24A370091