4-perfect (quadruply-perfect or sous-triple) numbers: sum of divisors of n is 4n.

A027687

4-perfect (quadruply-perfect or sous-triple) numbers: sum of divisors of n is 4n.

Terms

    a(0) =30240a(1) =32760a(2) =2178540a(3) =23569920a(4) =45532800a(5) =142990848a(6) =1379454720a(7) =43861478400a(8) =66433720320a(9) =153003540480a(10) =403031236608a(11) =704575228896

External references