Numbers k such that sigma(k)-2*k = phi(k): abundance of k equals Eulerphi of k.

A088826

Numbers k such that sigma(k)-2*k = phi(k): abundance of k equals Eulerphi of k.

Terms

    a(0) =12a(1) =42a(2) =1242a(3) =6137440a(4) =1385119360a(5) =1588268480

External references