a(n) = {n concatenate R(n)}*{ R(n) concatenate n}, where R(n) = digit reversal of n.

Terms

a(0) =0a(1) =121a(2) =484a(3) =1089a(4) =1936a(5) =3025a(6) =4356a(7) =5929a(8) =7744a(9) =9801a(10) =110110a(11) =1234321a(12) =2578752a(13) =4143403a(14) =5928274a(15) =7933365a(16) =10158676a(17) =12604207a(18) =15269958a(19) =18155929a(20) =440440a(21) =2578752a(22) =4937284a(23) =7516036a(24) =10315008a(25) =13334200a(26) =16573612a(27) =20033244a(28) =23713096a(29) =27613168