Trajectory of 15 under map x->x + (x-with-digits-reversed).

Terms

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