bonanova Posted March 23, 2008 Report Share Posted March 23, 2008 My 1000th post. Maybe I should give my keyboard a rest. 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] Quote Link to comment Share on other sites More sharing options...
0 unreality Posted March 25, 2008 Report Share Posted March 25, 2008 1. send me the file and I will upload it if it's ok you mean via email? What email address should I send it to? Quote Link to comment Share on other sites More sharing options...
0 Guest Posted March 25, 2008 Report Share Posted March 25, 2008 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! Quote Link to comment Share on other sites More sharing options...
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bonanova
My 1000th post.
Maybe I should give my keyboard a rest.
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:
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