a(n) is the smallest number k such that sigma(k) - phi(k) = n*k, or 0 if no such k exists.
A291258
a(n) is the smallest number k such that sigma(k) - phi(k) = n*k, or 0 if no such k exists.
Terms
- a(0) =1a(1) =2a(2) =12a(3) =75960a(4) =17156160
External references
- oeis: A291258