Smallest k for which the number of divisors d of k such that A000005(d*k) = A000005(k + d) is equal to n, or -1 if no such k exists.

A389254

Smallest k for which the number of divisors d of k such that A000005(d*k) = A000005(k + d) is equal to n, or -1 if no such k exists.

Terms

    a(0) =1a(1) =4a(2) =2a(3) =98a(4) =1269a(5) =8019a(6) =149144a(7) =2144779a(8) =17271711a(9) =5403125

External references