Numbers k such that tau(sigma(k)) = rad(k).

Terms

a(0) =1a(1) =2a(2) =3a(3) =4a(4) =6a(5) =12a(6) =16a(7) =48a(8) =64a(9) =81a(10) =162a(11) =192a(12) =270a(13) =324a(14) =750a(15) =1029a(16) =1296a(17) =1512a(18) =2058a(19) =4096a(20) =4116a(21) =5184a(22) =12288a(23) =16464a(24) =65536a(25) =65856a(26) =196608a(27) =262144a(28) =331776a(29) =786432