3-smooth numbers whose arithmetic derivatives are also 3-smooth.

Terms

a(0) =2a(1) =3a(2) =4a(3) =8a(4) =9a(5) =12a(6) =16a(7) =27a(8) =54a(9) =64a(10) =81a(11) =108a(12) =144a(13) =256a(14) =432a(15) =512a(16) =729a(17) =972a(18) =1728a(19) =2916a(20) =3072a(21) =3456a(22) =4096a(23) =6561a(24) =11664a(25) =19683a(26) =20736a(27) =23328a(28) =27648a(29) =65536