Multi-perfect numbers m from A007691 such that m*(m-tau(m))/sigma(m) is an integer h, where k-tau(k) is the number of nondivisors of k (A049820) and sigma(k) is the sum of the divisors of k (A000203).

A325023

Multi-perfect numbers m from A007691 such that m*(m-tau(m))/sigma(m) is an integer h, where k-tau(k) is the number of nondivisors of k (A049820) and sigma(k) is the sum of the divisors of k (A000203).

Terms

    a(0) =1a(1) =6a(2) =28a(3) =496a(4) =672a(5) =8128a(6) =30240a(7) =32760a(8) =2178540a(9) =23569920a(10) =33550336a(11) =45532800a(12) =142990848a(13) =1379454720a(14) =8589869056a(15) =14182439040a(16) =43861478400a(17) =66433720320a(18) =137438691328a(19) =153003540480a(20) =403031236608a(21) =704575228896

External references