Squares that remain squares when prefixed with a 9.

Terms

a(0) =3025a(1) =50625a(2) =70225a(3) =302500a(4) =455625a(5) =765625a(6) =2640625a(7) =5062500a(8) =7022500a(9) =30250000a(10) =45562500a(11) =76562500a(12) =264062500a(13) =506250000a(14) =702250000a(15) =3025000000a(16) =4556250000a(17) =7656250000a(18) =26406250000a(19) =34363890625a(20) =50625000000a(21) =70225000000a(22) =302500000000a(23) =455625000000