The sequence obtained from reversing the digits of a number 
and adding the result to the original number. For 
, 2, ..., this gives 2, 4, 6, 8, 10, 12, 14, 16, 18, 11,
22, 33, 44, 55, 66, 77, 88, 99, 110, ... (OEIS A056964).
Looking at iterations of the reverse-then-add algorithm in base-2 gives the visualizations illustrated above, it which the left plot begins with 16 and runs 250 steps and the right plot begins with 512 and runs 500 steps (Wolfram 2002, pp. 125-127).
Applying the reverse-then-add operating iteratively until a palindromic number is obtained is called the 196-algorithm.
