Numbers k such that rad(k)^2 divides sigma(k).

Terms

a(0) =1a(1) =96a(2) =864a(3) =1080a(4) =1782a(5) =6144a(6) =7128a(7) =7776a(8) =17280a(9) =27000a(10) =28512a(11) =54432a(12) =55296a(13) =69984a(14) =87480a(15) =114048a(16) =215622a(17) =276480a(18) =381024a(19) =393216a(20) =432000a(21) =433026a(22) =456192a(23) =497664a(24) =629856a(25) =675000a(26) =862488a(27) =1382400a(28) =1399680a(29) =1677312