Exclusionary squares.

Terms

a(0) =4a(1) =9a(2) =16a(3) =49a(4) =64a(5) =81a(6) =289a(7) =324a(8) =576a(9) =841a(10) =1156a(11) =1444a(12) =1521a(13) =2209a(14) =2809a(15) =2916a(16) =3249a(17) =3364a(18) =3481a(19) =3844a(20) =4489a(21) =5184a(22) =6241a(23) =7056a(24) =8464a(25) =8836a(26) =24649a(27) =24964a(28) =29929a(29) =34969