Pseudoperfect (or semiperfect) numbers k: some subset of the proper divisors of k sums to k.

Terms

a(0) =6a(1) =12a(2) =18a(3) =20a(4) =24a(5) =28a(6) =30a(7) =36a(8) =40a(9) =42a(10) =48a(11) =54a(12) =56a(13) =60a(14) =66a(15) =72a(16) =78a(17) =80a(18) =84a(19) =88a(20) =90a(21) =96a(22) =100a(23) =102a(24) =104a(25) =108a(26) =112a(27) =114a(28) =120a(29) =126