| 
REVERSAL-ADDITION
PALINDROME
TEST ON 
167
 |   
Reverse and Add Process:
  
1. Pick a number. 
2. Reverse its digits and add this value to the original number. 
3. If this is not a palindrome, go back to step 2 and repeat. 
 |  | Let's view this Reverse and Add sequence starting with 167: |  
167 
+ 761 
step 1: 928 
+ 829 
step 2: 1757 
+ 7571 
step 3: 9328 
+ 8239 
step 4: 17567 
+ 76571 
step 5: 94138 
+ 83149 
step 6: 177287 
+ 782771 
step 7: 960058 
+ 850069 
step 8: 1810127 
+ 7210181 
step 9: 9020308 
+ 8030209 
step 10: 17050517 
+ 71505071 
step 11: 88555588 
 |  
  |  
 | 
167 takes 11 iterations / steps to resolve into a 8 digit palindrome.
 |  
  
| 
REVERSAL-ADDITION
PALINDROME
RECORDS
 |   
 
Most Delayed Palindromic Number for each digit length 
(Only iteration counts for which no smaller records exist are considered.
My program records only the smallest number that resolves for each distinct iteration count.
For example, there are 18-digit numbers that resolve in 232 iterations,
higher than the 228 iteration record shown for 18-digit numbers, but they were not recorded,
as a smaller [17-digit] number already holds the record for 232 iterations.)
  
| Digits | Number | Result |  
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
 | 
89 
187 
1,297 
10,911 
150,296 
9,008,299 
10,309,988 
140,669,390 
1,005,499,526 
10,087,799,570 
100,001,987,765 
1,600,005,969,190 
14,104,229,999,995 
100,120,849,299,260 
1,030,020,097,997,900 
10,442,000,392,399,960 
170,500,000,303,619,996 
1,186,060,307,891,929,990 
 | 
solves in 24 iterations. 
solves in 23 iterations. 
solves in 21 iterations. 
solves in 55 iterations. 
solves in 64 iterations. 
solves in 96 iterations. 
solves in 95 iterations. 
solves in 98 iterations. 
solves in 109 iterations. 
solves in 149 iterations. 
solves in 143 iterations. 
solves in 188 iterations. 
solves in 182 iterations. 
solves in 201 iterations. 
solves in 197 iterations. 
solves in 236 iterations. 
solves in 228 iterations. 
solves in 261 iterations - World Record! 
 | 
 
| [View all records] |  
  
This reverse and add program was created by Jason Doucette. 
Please visit my Palindromes and World Records page. 
You have permission to use the data from this webpage (with due credit). A link to my website is much appreciated. Thank you. 
 (This program has been run Indeterminable times since Saturday, March 9th, 2002.)
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