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bonanova

Question

My 1000th post. :o

Maybe I should give my keyboard a rest. :huh:

Anyway Happy Easter, and here's a little gem for you.

Take a number N, reverse its digits and add it to N.

Repeat if necessary. Eventually you will get a palindrome.

For example, starting with 39, we have 39 + 93 = 132.

Then 132 + 231 = 363 = palindrome.

After a moment's thought, this is not surprising.

But sometimes you do have to be patient.

Consider the starting number 89:

					  89	  ------>   159487405
187 | 664272356
968 | 1317544822
1837 | 3602001953
9218 | 7193004016
17347 | 13297007933
91718 | 47267087164
173437 | 93445163438
907808 | 176881317877
1716517 | 955594506548
8872688 | 1801200002107
17735476 | 8813200023188 = palindrome!
85189247 --->[/code]

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bona and unreality - I don't know if you've seen this yet but it looks like we've just stumbled upon the tip of the iceberg. This guy has been running computer programs for over a decade to compute the largest iterations of palindromic numbers.

World Records

I was going to sit down and ponder a proof, but that site really discouraged me. Perhaps it is a good thing. I should probably spend that amount of time on something else. Loved this topic, though! :)

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