REVERSAL-ADDITION PALINDROME TEST ON 1009246

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 1009246:
1009246
+ 6429001
step 1: 7438247
+ 7428347
step 2: 14866594
+ 49566841
step 3: 64433435
+ 53433446
step 4: 117866881
+ 188668711
step 5: 306535592
+ 295535603
step 6: 602071195
+ 591170206
step 7: 1193241401
+ 1041423911
step 8: 2234665312
+ 2135664322
step 9: 4370329634
+ 4369230734
step 10: 8739560368
+ 8630659378
step 11: 17370219746
+ 64791207371
step 12: 82161427117
+ 71172416128
step 13: 153333843245
+ 542348333351
step 14: 695682176596
+ 695671286596
step 15: 1391353463192
+ 2913643531931
step 16: 4304996995123
+ 3215996994034
step 17: 7520993989157
+ 7519893990257
step 18: 15040887979414
+ 41497978804051
step 19: 56538866783465
+ 56438766883565
step 20: 112977633667030
+ 030766336779211
step 21: 143743970446241
+ 142644079347341
step 22: 286388049793582
+ 285397940883682
step 23: 571785990677264
+ 462776099587175
step 24: 1034562090264439
+ 9344620902654301
step 25: 10379182992918740
+ 04781929928197301
step 26: 15161112921116041
+ 14061112921116151
step 27: 29222225842232192
+ 29123224852222292
step 28: 58345450694454484
+ 48445449605454385
step 29: 106790900299908869
+ 968809992009097601
step 30: 1075600892309006470
+ 0746009032980065701
step 31: 1821609925289072171
+ 1712709825299061281
step 32: 3534319750588133452
+ 2543318850579134353
step 33: 6077638601167267805
+ 5087627611068367706
step 34: 11165266212235635511
+ 11553653221266256111
step 35: 22718919433501891622
+ 22619810533491981722
step 36: 45338729966993873344
+ 44337839966992783354
step 37: 89676569933986656698
+ 89665668933996567698
step 38: 179342238867983224396
+ 693422389768832243971
step 39: 872764628636815468367
+ 763864518636826467278
step 40: 1636629147273641935645
+ 5465391463727419266361
step 41: 7102020611001061202006
+ 6002021601001160202017
step 42: 13104042212002221404023
+ 32040412220021224040131
step 43: 45144454432023445444154
1009246 takes 43 iterations / steps to resolve into a 23 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.)

DigitsNumberResult
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 2,550,026 times since Saturday, March 9th, 2002.)