Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (2,8)-perfect numbers.

A019285

Let sigma_m (n) be result of applying sum-of-divisors function m times to n; call n (m,k)-perfect if sigma_m (n) = k*n; sequence gives the (2,8)-perfect numbers.

Terms

    a(0) =60a(1) =240a(2) =960a(3) =4092a(4) =16368a(5) =58254a(6) =61440a(7) =65472a(8) =116508a(9) =466032a(10) =710400a(11) =983040a(12) =1864128a(13) =3932160a(14) =4190208a(15) =67043328a(16) =119304192a(17) =268173312a(18) =1908867072a(19) =7635468288a(20) =16106127360a(21) =711488165526

External references