 The 196 Algorithm - Maple Help

The 196-Algorithm

Main Concept

A palindromic number is a number that remains the same when its digits are reversed, such as 0, 1, 11, 121, 3773, etc. The 196-Algorithm is a procedure which quickly produces palindromic numbers for most positive integers.

This algorithm relies on the operation of the "reverse-then-add" sequence, instructing us to:

 • choose any positive integer of two or more digits
 • reverse the digits of this number
 • add this reversed number to the original number

If the result is a palindromic number, then this process is complete. If not, repeat this process on the resulting number and keep on repeating it until a palindromic number is reached.

It is suspected that there are some positive integers for which this algorithm never produces a palindromic number. These integers are known as Lychrel numbers. Since 196 is considered to be the first Lychrel number, the algorithm was named after it.

Enter a positive integer of two digits or more in the box below and click "Apply Algorithm" to apply the 196-Algorithm. Can you find any Lychrel numbers?   More MathApps