Tool to test Lychrel numbers. A Lychrel number is a natural integer which does not end the iterative process : while a number is not a palindrom, add the number to its mirror (created by reversing the order of its digits) in order to obtain a new number.

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Tool to test Lychrel numbers. A Lychrel number is a natural integer which does not end the iterative process : while a number is not a palindrom, add the number to its mirror (created by reversing the order of its digits) in order to obtain a new number.

Answers to Questions

How to calculate iterations of a Lychrel number?

If one adds a number to the value of its mirror (the order of its digits are reversed) to obtain a new number. If this number is a new palindrome, it stops, else one starts again with this number.

360 + 063 = 423 423 + 324 = 747

What are the Lychrel numbers?

Lychrel numbers never creates such a palindrome, the smaller is 196. It is supposed that there are an infinite number of Lychrel numbers.

What is the number the most delayed?

A number is delayed when there a multiple steps before becoming a palindrome. The most delayed known is 1186060307891929990 with 261 itérations.

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Source code

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