Lychrel Numbers

The Lychrel Numbers nBAB collection was created on 30 August 2015. A Lychrel Number is a "positive integer that apparently never results in a palindrome under repeated applications of the function f(x) = x + (x with digits reversed)". {OEIS.org::A023108}

There are 76 Lychrel Numbers that are less than 5000. Four of these 76 Lychrel Numbers had nBABs when the Lychrel Numbers collection was created.

This C++ program was written to generate the Lychrel Numbers.

Wikipedia.org... "The name Lychrel was coined by Wade VanLandingham as a rough anagram of Cheryl, his girlfriend's first name."

The Lychrel Number Story

29 August 2015: I watched YouTube.com::Numberphile::What's special about 196?

29 August 2015: A program is written to create the Lychrel Numbers collection.

30 August 2015: The MBNA (MathBabbler Number Analyst) started checking for Lychrel Numbers.

31 August 2015: nBAB for the number 295 was created because it was the smallest Lychrel Number that didn't have a nBAB.


Creator: Gerald Thurman [gthurman@gmail.com]
Created: 30 August 2015 (posted 31 August 2015)

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