Values square, differences triangular.

Terms

a(0) =0a(1) =1a(2) =4a(3) =25a(4) =196a(5) =1681a(6) =2116a(7) =18769a(8) =168100a(9) =1510441a(10) =13586596a(11) =14577124a(12) =15856324a(13) =16120225a(14) =16289296a(15) =16736281a(16) =150601984a(17) =151782400a(18) =1365967681a(19) =1368334081a(20) =1393379584a(21) =1640655025a(22) =1649578225a(23) =1669212736a(24) =1725737764