408404

Appears in sequences

• Numbers n such that usigma(usigma(n))/usigma(n) > usigma(usigma(m))/usigma(m) for all m < n, where usigma(n) is the sum of unitary divisors of n (A034448).at n=7A289126
• a(n) is the smallest k such that usigma(k) = A002110(n), or 0 if no such k exists.at n=7A291356