Squares that becomes primes when prefixed with a 3.

Terms

a(0) =1a(1) =49a(2) =121a(3) =169a(4) =361a(5) =529a(6) =1849a(7) =2401a(8) =3721a(9) =6241a(10) =8281a(11) =9409a(12) =11881a(13) =14161a(14) =14641a(15) =19321a(16) =20449a(17) =25921a(18) =27889a(19) =39601a(20) =49729a(21) =51529a(22) =52441a(23) =69169a(24) =76729a(25) =83521a(26) =89401a(27) =94249a(28) =104329a(29) =113569