Refactorable numbers that are twice a square.

Terms

a(0) =2a(1) =8a(2) =18a(3) =72a(4) =128a(5) =288a(6) =450a(7) =882a(8) =1152a(9) =1250a(10) =1800a(11) =2178a(12) =3042a(13) =3528a(14) =4050a(15) =5000a(16) =5202a(17) =6498a(18) =8712a(19) =9522a(20) =11250a(21) =12168a(22) =13122a(23) =15138a(24) =16200a(25) =17298a(26) =18432a(27) =20808a(28) =24642a(29) =25992