Numbers m such that phi(m) * sigma(m) + k^2 is not a square for any k.

Terms

a(0) =4a(1) =9a(2) =18a(3) =49a(4) =81a(5) =98a(6) =121a(7) =162a(8) =242a(9) =361a(10) =529a(11) =722a(12) =729a(13) =961a(14) =1058a(15) =1458a(16) =1849a(17) =1922a(18) =2209a(19) =2401a(20) =3481a(21) =3698a(22) =4418a(23) =4489a(24) =4802a(25) =5041a(26) =6241a(27) =6561a(28) =6889a(29) =6962