Composite n such that (n-1)*phi(n) is a perfect square.

Terms

a(0) =10a(1) =28a(2) =51a(3) =170a(4) =243a(5) =246a(6) =946a(7) =1128a(8) =1281a(9) =1353a(10) =1695a(11) =2431a(12) =4336a(13) =4411a(14) =4625a(15) =4803a(16) =7501a(17) =7936a(18) =8625a(19) =11914a(20) =12545a(21) =13255a(22) =15051a(23) =16385a(24) =24643a(25) =27870a(26) =29404a(27) =31828a(28) =33490a(29) =36751