Definition:Lychrel Number/Historical Note

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Historical Note on Lychrel Number

David Wells, reporting on the state of play in $1986$ in his Curious and Interesting Numbers, noted that P.C. Leyland had performed $50 \, 000$ reversals, which produced a number of over $26 \, 000$ digits, still not palindromic.

The same source reported that P. Anderson had continued the search to $70 \, 928$ digits without any success at reaching a palindrome.

By $1997$, in his Curious and Interesting Numbers, 2nd ed., he was able to report that John Walker and Tim Irvin had carried the process for $196$ to over one million digits, which was reached after $2 \, 415 \, 836$ reverse-and-add iterations, which took $3$ years of spare time on a Sun $3/260$.

They subsequently continued the work, taking the calculation to $2 \, 000 \, 000$ digits on a supercomputer, taking a mere $2$ months.

Still no sign of termination.

The term Lychrel number was coined in $2002$ by Wade VanLandingham, as a near-anagram of the name of his girlfriend Cheryl.

It's anyone's guess how to pronounce it.