Perfect squares that are a product of two triangular numbers.

Terms

a(0) =1a(1) =9a(2) =36a(3) =100a(4) =225a(5) =441a(6) =784a(7) =900a(8) =1225a(9) =1296a(10) =2025a(11) =3025a(12) =4356a(13) =6084a(14) =7056a(15) =8281a(16) =11025a(17) =14400a(18) =18496a(19) =23409a(20) =29241a(21) =32400a(22) =36100a(23) =41616a(24) =44100a(25) =53361a(26) =64009a(27) =76176a(28) =88209a(29) =90000