Numbers k such that phi(sigma(k^3)) is a square.

Terms

a(0) =1a(1) =3a(2) =10a(3) =14a(4) =21a(5) =49a(6) =66a(7) =70a(8) =147a(9) =160a(10) =224a(11) =248a(12) =282a(13) =330a(14) =403a(15) =462a(16) =490a(17) =764a(18) =803a(19) =817a(20) =1034a(21) =1056a(22) =1120a(23) =1235a(24) =1508a(25) =1512a(26) =1584a(27) =1752a(28) =1779a(29) =1792