16522145640
domain: N
Appears in sequences
- Smallest x such that sigma(x) = n*phi(x), or -1 if no such x exists.at n=29A055234
- a(n) = Min {x : sigma(x) = phi(n*x), x is not a prime}, least nonprime solutions to sigma(x) = phi(n*x).at n=29A087979
- a(n) = Min{x : sigma(x) = n*phi(x), x is not a prime}, the least nonprime solutions to sigma(x) = n*phi(x); special balanced numbers.at n=29A088830
- a(n) is the least number k > 0 such that sigma(k/n) = phi(k).at n=28A241762
- a(n) is the least number k > 0 such that sigma(k) = phi(n*k).at n=29A256527
- Balanced numbers (A020492) k with a record value of sigma(k)/phi(k).at n=16A335287