Trajectory of 3 under map x->x + (x-with-digits-reversed).

Terms

a(0) =3a(1) =6a(2) =12a(3) =33a(4) =66a(5) =132a(6) =363a(7) =726a(8) =1353a(9) =4884a(10) =9768a(11) =18447a(12) =92928a(13) =175857a(14) =934428a(15) =1758867a(16) =9447438a(17) =17794887a(18) =96644658a(19) =182289327a(20) =906271608a(21) =1712444217a(22) =8836886388a(23) =17673772776a(24) =85401510447a(25) =159803020905a(26) =668823329856