a(n) = the smallest positive multiple of n that has exactly n 1's in its binary representation.

Terms

a(0) =1a(1) =6a(2) =21a(3) =60a(4) =55a(5) =126a(6) =623a(7) =2040a(8) =1503a(9) =3070a(10) =3839a(11) =16380a(12) =16367a(13) =94206a(14) =96255a(15) =1048560a(16) =483327a(17) =524286a(18) =1040383a(19) =4194300a(20) =5767167a(21) =16515070a(22) =16252927a(23) =134217720a(24) =66584575a(25) =251658238a(26) =402651135a(27) =5234491388a(28) =1073741791