| Kaprekar Sequences |
The original idea for Kaprekar numbers defined them roughly as follows:
Definition A: N is a Kaprekar number if it has D digits, and if you take N2 and divide it into two pieces each D digits in size and add them together, you get N.
For example: 452 = 2025, and 20+25 = 45, so 45 is a Kaprekar number.
Here is an example of a Kaprekar number for cubes: 71723 = 368910352448 and 3689+1035+2448 = 7172. There are also solutions for higher powers.
On this page Douglas E. Iannucci explains how the Kaprekar numbers (for squares) can be derived from the prime factorization of 10D-1. He also shows that if N is a Kaprekar number of D digits, then 10D-N is also a Kaprekar number of D digits. Thus, for example, since 45 is a 2-digit Kaprekar number we know that 55 is as well because 45+55 = 100. However, this only holds true if you allow Kaprekar numbers to start with zero, such as the "five-digit" example 048792=0023804641, 00238+04641=04879 (with small 0's added to show that 4879 is being treated as a 5-digit number). If such numbers were not allowed, the symmetry would break down: 95121 is also a Kaprekar number and 95121+04879 = 105.
Because of this, the definition of the Kaprekar numbers is usually given somewhat like this:
Definiton B: N is a Kaprekar number if there are three numbers
D>0, 0<=Q and 0<=R<10D
such that N2=Q×10D+R and Q+R=N.
This definition allows the 048792 solution, and also allows the solution N=10, D=1, Q=10, R=0 (which takes 102=100 and divides it into two pieces like this: 10 0).
Although the reasons for Definition B are well-justified by the mathematics showing how to derive all the Kaprekar numbers, these reasons disappear when we discuss Kaprekar numbers for cubes and higher powers, where the aforementioned symmetry does not exist. Also, Definition B does not follow the intuitive nature of definition A: D should be the number of digits in N, neither more (as with 04879) nor less (as with the bogus 102=100 example). The definition can be brought in line with Definition A by explicitly stating that D is the number of digits in N:
Definiton C: N is a Kaprekar number if there are three numbers
D>0, 0<=Q and 0<=R<10D
such that 10D-1 <= N < 10D,
N2=Q×10D+R and Q+R=N.
In order to prevent further confusion I will call these the "natural Kaprekar numbers".
There are also definitions that add additional requirements for R, and perhaps Q as well, to be D-digit numbers. They are apparently intended to prevent the 102=10 0 case, but also prevent legitimate Kaprekar numbers like 9992=998001, 998+001=999 and 2973 = 26198073, 26+198+073 = 297.
Not all of the variations of each Kaprekar sequence are included in Sloane's catalog. In particular, the natural versions are lacking or labeled "incorrect". Since the other sequences can very easily be derived from the natural sequence, I will give only that version.
Here are the natural Kaprekar numbers:
For squares: 1, 9, 45, 55, 99, 297, 703, 999, 2223, 2728, 4950, 5050, 7272, 7777, 9999, 17344, 22222, 77778, 82656, 95121, 99999, 142857, 148149, 181819, 187110, 208495, 318682, 329967, 351352, 356643, 390313, 461539, 466830, 499500, 500500, 533170, 538461, 609687, 643357, 648648, 670033, 681318, 791505, 812890, 818181, 851851, 857143, 961038, 994708, 999999, 4444444, 4927941, 5072059, 5555556, 9372385, 9999999, 11111112, 13641364, 16590564, 19273023, 19773073, 24752475, 25252525, 30884184, 36363636, 38883889, 44363341, 44525548, 49995000, 50005000, 55474452, 55636659, 61116111, 63636364, 69115816, 74747475, 75247525, 80226927, 80726977, 83409436, 86358636, 88888888, 91838088, 94520547, 99999999, 234567901, 332999667, 432432432, 567567568, 667000333, 765432099, 999999999, 1111111111, 1776299581, 2020202020, 3846956652, 3888938889, 4090859091, 4132841328, ...
For 3rd powers: 1, 8, 10, 45, 297, 2322, 2728, 4445, 4544, 4949, 5049, 5455, 5554, 7172, 27100, 44443, 55556, 60434, 77778, 143857, 208494, 226071, 279720, 313390, 324675, 329967, 346060, 368928, 395604, 422577, 427868, 461539, 472823, 478115, 488214, 494208, 495208, 499500, 500500, 517076, 533170, 543752, 559846, 565137, 598807, 664741, 670032, 720279, 757835, 791505, 807598, 825175, 829466, 856142, 966329, 973323, 4444443, 4927940, 5072058, 5555555, 5555556, 5699673, 6183170, 8888887, 11273318, 13793570, 17090613, 21803275, 22293325, 24752475, 25242525, 25252524, 27272728, 27282727, 28201724, 30731977, 33404436, 36363635, 38383839, 38546045, 38883889, 39046095, 39546145, 41843088, 44025497, 44363340, 44525547, 45025597, 47045800, 49842793, 49995000, 50005000, 50657256, 55474451, 55474452, 55484452, 56136708, 58156911, 58656961, 60453854, 61453954, 63636364, 63798570, 64298620, 66747770, 69278022, 69768072, 69778072, 72227222, 72717272, 72727271, 74747475, 74909681, 75409731, 77706674, 77767777, 77777776, 80726976, 80726977, 80889183, 88878888, 88888888, 93868290, 197864531, 332999667, 667000332, ...
For 4th powers: 1, 7, 45, 55, 67, 100, 433, 4950, 5050, 38212, 65068, 190576, 295075, 299035, 310024, 336700, 343333, 394615, 414558, 433566, 448228, 450550, 467236, 475497, 476191, 486486, 499500, 500500, 523513, 534898, 549550, 599743, 622414, 628408, 647362, 652015, 671671, 677755, 705331, 731368, 734932, 765963, 772200, 803539, 820612, 826606, 849520, 934066, 25280200, 33333334, 44525548, 49995000, 50005000, 55474452, 58585858, 61643836, 77696674, 332999667, 334333333, 811144477, 3577235773, ...
For 5th powers: 1, 10, 1000, 7776, 27100, 73440, 95120, 500499, 505791, 540539, 598697, 665335, 697598, 732347, 7607610, 37944478, 46945205, 54995500, 55216205, 56607166, ...
Table of expansions of normal (order-2) Kaprekar numbers:
12 = 1 ; 0 + 1 = 0
92 = 81 ; 8 + 1 = 8
452 = 2025 ; 20 + 25 = 20
552 = 3025 ; 30 + 25 = 30
992 = 9801 ; 98 + 01 = 98
2972 = 88209 ; 088 + 209 = 88
7032 = 494209 ; 494 + 209 = 494
9992 = 998001 ; 998 + 001 = 998
22232 = 4941729 ; 0494 + 1729 = 494
27282 = 7441984 ; 0744 + 1984 = 744
49502 = 24502500 ; 2450 + 2500 = 2450
50502 = 25502500 ; 2550 + 2500 = 2550
72722 = 52881984 ; 5288 + 1984 = 5288
77772 = 60481729 ; 6048 + 1729 = 6048
99992 = 99980001 ; 9998 + 0001 = 9998
173442 = 300814336 ; 03008 + 14336 = 3008
222222 = 493817284 ; 04938 + 17284 = 4938
777782 = 6049417284 ; 60494 + 17284 = 60494
826562 = 6832014336 ; 68320 + 14336 = 68320
951212 = 9048004641 ; 90480 + 04641 = 90480
999992 = 9999800001 ; 99998 + 00001 = 99998
1428572 = 20408122449 ; 020408 + 122449 = 20408
1481492 = 21948126201 ; 021948 + 126201 = 21948
1818192 = 33058148761 ; 033058 + 148761 = 33058
1871102 = 35010152100 ; 035010 + 152100 = 35010
2084952 = 43470165025 ; 043470 + 165025 = 43470
3186822 = 101558217124 ; 101558 + 217124 = 101558
3299672 = 108878221089 ; 108878 + 221089 = 108878
3513522 = 123448227904 ; 123448 + 227904 = 123448
3566432 = 127194229449 ; 127194 + 229449 = 127194
3903132 = 152344237969 ; 152344 + 237969 = 152344
4615392 = 213018248521 ; 213018 + 248521 = 213018
4668302 = 217930248900 ; 217930 + 248900 = 217930
4995002 = 249500250000 ; 249500 + 250000 = 249500
5005002 = 250500250000 ; 250500 + 250000 = 250500
5331702 = 284270248900 ; 284270 + 248900 = 284270
5384612 = 289940248521 ; 289940 + 248521 = 289940
6096872 = 371718237969 ; 371718 + 237969 = 371718
6433572 = 413908229449 ; 413908 + 229449 = 413908
6486482 = 420744227904 ; 420744 + 227904 = 420744
6700332 = 448944221089 ; 448944 + 221089 = 448944
6813182 = 464194217124 ; 464194 + 217124 = 464194
7915052 = 626480165025 ; 626480 + 165025 = 626480
8128902 = 660790152100 ; 660790 + 152100 = 660790
8181812 = 669420148761 ; 669420 + 148761 = 669420
8518512 = 725650126201 ; 725650 + 126201 = 725650
8571432 = 734694122449 ; 734694 + 122449 = 734694
9610382 = 923594037444 ; 923594 + 037444 = 923594
9947082 = 989444005264 ; 989444 + 005264 = 989444
9999992 = 999998000001 ; 999998 + 000001 = 999998
44444442 = 19753082469136 ; 1975308 + 2469136 = 1975308
49279412 = 24284602499481 ; 2428460 + 2499481 = 2428460
50720592 = 25725782499481 ; 2572578 + 2499481 = 2572578
55555562 = 30864202469136 ; 3086420 + 2469136 = 3086420
93723852 = 87841600588225 ; 8784160 + 0588225 = 8784160
99999992 = 99999980000001 ; 9999998 + 0000001 = 9999998
111111122 = 123456809876544 ; 01234568 + 09876544 = 1234568
136413642 = 186086811780496 ; 01860868 + 11780496 = 1860868
165905642 = 275246813838096 ; 02752468 + 13838096 = 2752468
192730232 = 371449415558529 ; 03714494 + 15558529 = 3714494
197730732 = 390974415863329 ; 03909744 + 15863329 = 3909744
247524752 = 612685018625625 ; 06126850 + 18625625 = 6126850
252525252 = 637690018875625 ; 06376900 + 18875625 = 6376900
308841842 = 953832821345856 ; 09538328 + 21345856 = 9538328
363636362 = 1322314023140496 ; 13223140 + 23140496 = 13223140
388838892 = 1511956823764321 ; 15119568 + 23764321 = 15119568
443633412 = 1968106024682281 ; 19681060 + 24682281 = 19681060
445255482 = 1982524424700304 ; 19825244 + 24700304 = 19825244
499950002 = 2499500025000000 ; 24995000 + 25000000 = 24995000
500050002 = 2500500025000000 ; 25005000 + 25000000 = 25005000
554744522 = 3077414824700304 ; 30774148 + 24700304 = 30774148
556366592 = 3095437824682281 ; 30954378 + 24682281 = 30954378
611161112 = 3735179023764321 ; 37351790 + 23764321 = 37351790
636363642 = 4049586823140496 ; 40495868 + 23140496 = 40495868
691158162 = 4776996021345856 ; 47769960 + 21345856 = 47769960
747474752 = 5587185018875625 ; 55871850 + 18875625 = 55871850
752475252 = 5662190018625625 ; 56621900 + 18625625 = 56621900
802269272 = 6436359815863329 ; 64363598 + 15863329 = 64363598
807269772 = 6516844815558529 ; 65168448 + 15558529 = 65168448
834094362 = 6957134013838096 ; 69571340 + 13838096 = 69571340
863586362 = 7457814011780496 ; 74578140 + 11780496 = 74578140
888888882 = 7901234409876544 ; 79012344 + 09876544 = 79012344
918380882 = 8434234407495744 ; 84342344 + 07495744 = 84342344
945205472 = 8934133805179209 ; 89341338 + 05179209 = 89341338
999999992 = 9999999800000001 ; 99999998 + 00000001 = 99999998
2345679012 = 55022100179545801 ; 055022100 + 179545801 = 55022100
3329996672 = 110888778222110889 ; 110888778 + 222110889 = 110888778
4324324322 = 186997808245434624 ; 186997808 + 245434624 = 186997808
5675675682 = 322132944245434624 ; 322132944 + 245434624 = 322132944
6670003332 = 444889444222110889 ; 444889444 + 222110889 = 444889444
7654320992 = 585886298179545801 ; 585886298 + 179545801 = 585886298
9999999992 = 999999998000000001 ; 999999998 + 000000001 = 999999998
11111111112 = 1234567900987654321 ; 0123456790 + 0987654321 = 123456790
17762995812 = 3155240201460775561 ; 0315524020 + 1460775561 = 315524020
20202020202 = 4081216201612080400 ; 0408121620 + 1612080400 = 408121620
38469566522 = 14799075482367049104 ; 1479907548 + 2367049104 = 1479907548
38889388892 = 15123845682376554321 ; 1512384568 + 2376554321 = 1512384568
40908590912 = 16735128102417346281 ; 1673512810 + 2417346281 = 1673512810
41328413282 = 17080377442424803584 ; 1708037744 + 2424803584 = 1708037744
(checked all bases through 4294967294)
Table of expansions of order-3 Kaprekar numbers:
13 = 1 ; 0+0+1 = 1
83 = 512 ; 5+1+2 = 8
103 = 1000 ; 0+10+00 = 10
453 = 91125 ; 9+11+25 = 45
2973 = 26198073 ; 26+198+073 = 297
23223 = 12519490248 ; 125+1949+0248 = 2322
27283 = 20301732352 ; 203+0173+2352 = 2728
44453 = 87824421125 ; 878+2442+1125 = 4445
45443 = 93824221184 ; 938+2422+1184 = 4544
49493 = 121213882349 ; 1212+1388+2349 = 4949
50493 = 128711132649 ; 1287+1113+2649 = 5049
54553 = 162324571375 ; 1623+2457+1375 = 5455
55543 = 171323771464 ; 1713+2377+1464 = 5554
71723 = 368910352448 ; 3689+1035+2448 = 7172
271003 = 19902511000000 ; 1990+25110+00000 = 27100
444433 = 87782935806307 ; 8778+29358+06307 = 44443
555563 = 171471879319616 ; 17147+18793+19616 = 55556
604343 = 220721185826504 ; 22072+11858+26504 = 60434
777783 = 470511577514952 ; 47051+15775+14952 = 77778
1438573 = 2977097087043793 ; 2977+097087+043793 = 143857
2084943 = 9063181647017784 ; 9063+181647+017784 = 208494
2260713 = 11554058606155911 ; 11554+058606+155911 = 226071
2797203 = 21886209834048000 ; 21886+209834+048000 = 279720
3133903 = 30779063611219000 ; 30779+063611+219000 = 313390
3246753 = 34225243575046875 ; 34225+243575+046875 = 324675
3299673 = 35926219978074063 ; 35926+219978+074063 = 329967
3460603 = 41443288617016000 ; 41443+288617+016000 = 346060
3689283 = 50214003962314752 ; 50214+003962+314752 = 368928
3956043 = 61913024827308864 ; 61913+024827+308864 = 395604
4225773 = 75460133084214033 ; 75460+133084+214033 = 422577
4278683 = 78330233506116032 ; 78330+233506+116032 = 427868
4615393 = 98316229404133819 ; 98316+229404+133819 = 461539
4728233 = 105705061351305767 ; 105705+061351+305767 = 472823
4781153 = 109294197946170875 ; 109294+197946+170875 = 478115
4882143 = 116367227503144344 ; 116367+227503+144344 = 488214
4942083 = 120706126590246912 ; 120706+126590+246912 = 494208
4952083 = 121440334856038912 ; 121440+334856+038912 = 495208
4995003 = 124625374875000000 ; 124625+374875+000000 = 499500
5005003 = 125375375125000000 ; 125375+375125+000000 = 500500
5170763 = 138249363851014976 ; 138249+363851+014976 = 517076
5331703 = 151564368606013000 ; 151564+368606+013000 = 533170
5437523 = 160769107975275008 ; 160769+107975+275008 = 543752
5598463 = 175471156639227736 ; 175471+156639+227736 = 559846
5651373 = 180493358291026353 ; 180493+358291+026353 = 565137
5988073 = 214714120150263943 ; 214714+120150+263943 = 598807
6647413 = 293736149984221021 ; 293736+149984+221021 = 664741
6700323 = 300806096458272768 ; 300806+096458+272768 = 670032
7202793 = 373682068958277639 ; 373682+068958+277639 = 720279
7578353 = 435235164725157875 ; 435235+164725+157875 = 757835
7915053 = 495862183018112625 ; 495862+183018+112625 = 791505
8075983 = 526727149679131192 ; 526727+149679+131192 = 807598
8251753 = 561873028927234375 ; 561873+028927+234375 = 825175
8294663 = 570684092086166696 ; 570684+092086+166696 = 829466
8561423 = 627534213320015288 ; 627534+213320+015288 = 856142
9663293 = 902350034690029289 ; 902350+034690+029289 = 966329
9733233 = 922085001971049267 ; 922085+001971+049267 = 973323
44444433 = 87791409602222606307 ; 877914+0960222+2606307 = 4444443
49279403 = 119673015472102184000 ; 1196730+1547210+2184000 = 4927940
50720583 = 130482609481202819112 ; 1304826+0948120+2819112 = 5072058
55555553 = 171467712620032578875 ; 1714677+1262003+2578875 = 5555555
55555563 = 171467805212623319616 ; 1714678+0521262+3319616 = 5555556
56996733 = 185161129138450934217 ; 1851611+2913845+0934217 = 5699673
61831703 = 236392428062461013000 ; 2363924+2806246+1013000 = 6183170
88888873 = 702331513854690480103 ; 7023315+1385469+0480103 = 8888887
112733183 = 1432700041661610713432 ;
143270+00416616+10713432 = 11273318
137935703 = 2624400123813012293000 ;
262440+01238130+12293000 = 13793570
170906133 = 4991980961501806976397 ;
499198+09615018+06976397 = 17090613
218032753 = 10364901934491001421875 ;
1036490+19344910+01421875 = 21803275
222933253 = 11079611748223903703125 ;
1107961+17482239+03703125 = 22293325
247524753 = 15165470606405317171875 ;
1516547+06064053+17171875 = 24752475
252425253 = 16084160018098423453125 ;
1608416+00180984+23453125 = 25242525
252525243 = 16103281230837211333824 ;
1610328+12308372+11333824 = 25252524
272727283 = 20285501247182612772352 ;
2028550+12471826+12772352 = 27272728
272827273 = 20307821247736212774583 ;
2030782+12477362+12774583 = 27282727
282017243 = 22429881232731213631424 ;
2242988+12327312+13631424 = 28201724
307319773 = 29024951215764915671833 ;
2902495+12157649+15671833 = 30731977
334044363 = 37274551844312511233856 ;
3727455+18443125+11233856 = 33404436
363636353 = 48084141848234613072875 ;
4808414+18482346+13072875 = 36363635
383838393 = 56551642990995602818719 ;
5655164+29909956+02818719 = 38383839
385460453 = 57271620577775827041125 ;
5727162+05777758+27041125 = 38546045
388838893 = 58790761308044419924369 ;
5879076+13080444+19924369 = 38883889
390460953 = 59529580178576231307375 ;
5952958+01785762+31307375 = 39046095
395461453 = 61846120636290826998625 ;
6184612+06362908+26998625 = 39546145
418430883 = 73260720125954433257472 ;
7326072+01259544+33257472 = 41843088
440254973 = 85332172405380711438473 ;
8533217+24053807+11438473 = 44025497
443633403 = 87311752792816507704000 ;
8731175+27928165+07704000 = 44363340
445255473 = 88272980485592630842323 ;
8827298+04855926+30842323 = 44525547
450255973 = 91280590244636533451173 ;
9128059+02446365+33451173 = 45025597
470458003 = 104126812463311912000000 ;
10412681+24633119+12000000 = 47045800
498427933 = 123824650720907130251257 ;
12382465+07209071+30251257 = 49842793
499950003 = 124962503749875000000000 ;
12496250+37498750+00000000 = 49995000
500050003 = 125037503750125000000000 ;
12503750+37501250+00000000 = 50005000
506572563 = 129994501742459020233216 ;
12999450+17424590+20233216 = 50657256
554744513 = 170717891744681120955851 ;
17071789+17446811+20955851 = 55474451
554744523 = 170717900976925428633408 ;
17071790+09769254+28633408 = 55474452
554844523 = 170810240065002037753408 ;
17081024+00650020+37753408 = 55484452
561367083 = 176905291183926726606912 ;
17690529+11839267+26606912 = 56136708
581569113 = 196699833740089701086031 ;
19669983+37400897+01086031 = 58156911
586569613 = 201817431964353718831681 ;
20181743+19643537+18831681 = 58656961
604538543 = 220938793708011101279864 ;
22093879+37080111+01279864 = 60453854
614539543 = 232086293635066101894664 ;
23208629+36350661+01894664 = 61453954
636363643 = 257700981126972226596544 ;
25770098+11269722+26596544 = 63636364
637985703 = 259676610203790935793000 ;
25967661+02037909+35793000 = 63798570
642986203 = 265830590578756131928000 ;
26583059+05787561+31928000 = 64298620
667477703 = 297378990157687135433000 ;
29737899+01576871+35433000 = 66747770
692780223 = 332496010036177335666648 ;
33249601+00361773+35666648 = 69278022
697680723 = 339601941949863016309248 ;
33960194+19498630+16309248 = 69768072
697780723 = 339747990397402531829248 ;
33974799+03974025+31829248 = 69778072
722272223 = 376792920320288231345048 ;
37679292+03202882+31345048 = 72227222
727172723 = 384514510655817327707648 ;
38451451+06558173+27707648 = 72717272
727272713 = 384673150653644527723511 ;
38467315+06536445+27723511 = 72727271
747474753 = 417627972518780307796875 ;
41762797+25187803+07796875 = 74747475
749096813 = 420352701580617017068241 ;
42035270+15806170+17068241 = 74909681
754097313 = 428827052296213509564891 ;
42882705+22962135+09564891 = 75409731
777066743 = 469218322003481810750024 ;
46921832+20034818+10750024 = 77706674
777677773 = 470326072320873707526433 ;
47032607+23208737+07526433 = 77767777
777777763 = 470507512318244907544576 ;
47050751+23182449+07544576 = 77777776
807269763 = 526085161987628408242176 ;
52608516+19876284+08242176 = 80726976
807269773 = 526085181538162612736833 ;
52608518+15381626+12736833 = 80726977
808891833 = 529262771767141910291487 ;
52926277+17671419+10291487 = 80889183
888788883 = 702094930154632317123072 ;
70209493+01546323+17123072 = 88878888
888888883 = 702331940521262213443072 ;
70233194+05212622+13443072 = 88888888
938682903 = 827097521036953800789000 ;
82709752+10369538+00789000 = 93868290
1978645313 = 7746470118484770071633291 ;
7746470+118484770+071633291 = 197864531
3329996673 = 36925926221999778074073963 ;
36925926+221999778+074073963 = 332999667
6670003323 = 296741406109664558260594368 ;
296741406+109664558+260594368 = 667000332
7654320983 = 448456177233250729083725192 ;
448456177+233250729+083725192 = 765432098
11111111103 = 1371742108367626890260631000 ;
13717421+0836762689+0260631000 = 1111111110
11530933483 = 1533180900156013471122160192 ;
15331809+0015601347+1122160192 = 1153093348
13550135503 = 2487888510162596650313875000 ;
24878885+1016259665+0313875000 = 1355013550
13969957873 = 2726373106688236530700908403 ;
27263731+0668823653+0700908403 = 1396995787
20202020193 = 8244881202309803481706772859 ;
82448812+0230980348+1706772859 = 2020202019
20202020203 = 8244881214553452080482408000 ;
82448812+1455345208+0482408000 = 2020202020
21126393083 = 9429226502268409311791506112 ;
94292265+0226840931+1791506112 = 2112639308
23060866963 = 12263851721309666430052481536 ;
0122638517+2130966643+0052481536 = 2306086696
26853904893 = 19365215722482381630243500169 ;
0193652157+2248238163+0243500169 = 2685390489
28874106913 = 24072748607741138341872569371 ;
0240727486+0774113834+1872569371 = 2887410691
(checked all bases through 2969000000)
Table of expansions of order-4 Kaprekar numbers:
14 = 1 ; 0+0+0+1 = 1
74 = 2401 ; 2+4+0+1 = 7
454 = 4100625 ; 4+10+06+25 = 45
554 = 9150625 ; 9+15+06+25 = 55
674 = 20151121 ; 20+15+11+21 = 67
1004 = 100000000 ; 0+100+000+000 = 100
4334 = 35152125121 ; 35+152+125+121 = 433
49504 = 600372506250000 ; 600+3725+0625+0000 = 4950
50504 = 650377506250000 ; 650+3775+0625+0000 = 5050
382124 = 2132058301111419136 ; 2132+05830+11114+19136 = 38212
650684 = 17925440300173701376 ; 17925+44030+01737+01376 = 65068
1905764 = 1319085144029937074176 ; 1319+085144+029937+074176 = 190576
2950754 = 7581055275091594140625 ; 7581+055275+091594+140625 = 295075
2990354 = 7996281784008630000625 ; 7996+281784+008630+000625 = 299035
3100244 = 9238070268138742091776 ; 9238+070268+138742+091776 = 310024
3367004 = 12852051748272100000000 ; 12852+051748+272100+000000 = 336700
3433334 = 13895116532078585134321 ; 13895+116532+078585+134321 = 343333
3946154 = 24249029288190453150625 ; 24249+029288+190453+150625 = 394615
4145584 = 29535287434085093012496 ; 29535+287434+085093+012496 = 414558
4335664 = 35336283531075963038736 ; 35336+283531+075963+038736 = 433566
4482284 = 40364161075126533120256 ; 40364+161075+126533+120256 = 448228
4505504 = 41207092837066506250000 ; 41207+092837+066506+250000 = 450550
4672364 = 47659028925138236252416 ; 47659+028925+138236+252416 = 467236
4754974 = 51120032934245362146081 ; 51120+032934+245362+146081 = 475497
4761914 = 51419130918046493247361 ; 51419+130918+046493+247361 = 476191
4864864 = 56012039572176486214416 ; 56012+039572+176486+214416 = 486486
4995004 = 62250374750062500000000 ; 62250+374750+062500+000000 = 499500
5005004 = 62750375250062500000000 ; 62750+375250+062500+000000 = 500500
5235134 = 75112096258305582046561 ; 75112+096258+305582+046561 = 523513
5348984 = 81862291297038523123216 ; 81862+291297+038523+123216 = 534898
5495504 = 91207142337066006250000 ; 91207+142337+066006+250000 = 549550
5997434 = 129378094625105339270401 ; 129378+094625+105339+270401 = 599743
6224144 = 150078130395081125260816 ; 150078+130395+081125+260816 = 622414
6284084 = 155943336115129054007296 ; 155943+336115+129054+007296 = 628408
6473624 = 175626000494277306193936 ; 175626+000494+277306+193936 = 647362
6520154 = 180730041458379202050625 ; 180730+041458+379202+050625 = 652015
6716714 = 203529043026143035282081 ; 203529+043026+143035+282081 = 671671
6777554 = 211004112934353192000625 ; 211004+112934+353192+000625 = 677755
7053314 = 247498110530114582232721 ; 247498+110530+114582+232721 = 705331
7313684 = 286117102194115281227776 ; 286117+102194+115281+227776 = 731368
7349324 = 291735063830077991301376 ; 291735+063830+077991+301376 = 734932
7659634 = 344216089001250585082161 ; 344216+089001+250585+082161 = 765963
7722004 = 355565151035265600000000 ; 355565+151035+265600+000000 = 772200
8035394 = 416896108155199047079441 ; 416896+108155+199047+079441 = 803539
8206124 = 453473020676298527047936 ; 453473+020676+298527+047936 = 820612
8266064 = 466868113631102411143696 ; 466868+113631+102411+143696 = 826606
8495204 = 520828128408040284160000 ; 520828+128408+040284+160000 = 849520
9340664 = 761220115590026520030736 ; 761220+115590+026520+030736 = 934066
252802004 = 408434126221501224961600000000 ;
408434+12622150+12249616+00000000 = 25280200
333333344 = 1234568000000002962963002469136 ;
1234568+00000000+29629630+02469136 = 33333334
445255484 = 3930403094533271344940217692416 ;
3930403+09453327+13449402+17692416 = 44525548
499950004 = 6247500374975000625000000000000 ;
6247500+37497500+06250000+00000000 = 49995000
500050004 = 6252500375025000625000000000000 ;
6252500+37502500+06250000+00000000 = 50005000
554744524 = 9470482003285202798303417692416 ;
9470482+00328520+27983034+17692416 = 55474452
585858584 = 11780702219802231731003707514896 ;
11780702+21980223+17310037+07514896 = 58585858
616438364 = 14439715129046200264868531650816 ;
14439715+12904620+02648685+31650816 = 61643836
776966744 = 36442630072556942449817409500176 ;
36442630+07255694+24498174+09500176 = 77696674
3329996674 = 12296321135592494172740531012370321 ;
12296321+135592494+172740531+012370321 = 332999667
3343333334 = 12494495111665332074519185135654321 ;
12494495+111665332+074519185+135654321 = 334333333
8111444774 = 432905259131466615113518762133253841 ;
432905259+131466615+113518762+133253841 = 811144477
35772357734 = 163753375309125813101733384260148885841 ;
163753375+3091258131+0173338426+0148885841 = 3577235773
(checked all bases through 3611622599)
Table of expansions of order-5 Kaprekar numbers:
15 = 1 ; 0+0+0+0+1 = 1
105 = 100000 ; 0+00+10+00+00 = 10
10005 = 1000000000000000 ; 0+1000+0000+0000+0000 = 1000
77765 = 28430288029929701376 ; 2843+0288+0299+2970+1376 = 7776
271005 = 14616603103510000000000 ; 146+16603+10351+00000+00000 = 27100
734405 = 2136305413264402022400000 ;
21363+05413+26440+20224+00000 = 73440
951205 = 7786803368050520883200000 ;
77868+03368+05052+08832+00000 = 95120
5004995 = 31406249062033782183750002499 ;
31406+249062+033782+183750+002499 = 500499
5057915 = 33102095432189229078077109951 ;
33102+095432+189229+078077+109951 = 505791
5405395 = 46146117682034200315812026699 ;
46146+117682+034200+315812+026699 = 540539
5986975 = 76919315312001453031756173257 ;
76919+315312+001453+031756+173257 = 598697
6653355 = 130377260305079059111219084375 ;
130377+260305+079059+111219+084375 = 665335
6975985 = 165206120951064038339435007968 ;
165206+120951+064038+339435+007968 = 697598
7323475 = 210661190534180357124288026507 ;
210661+190534+180357+124288+026507 = 732347
76076105 = 25482451314582286738507773980100000 ;
2548245+1314582+2867385+0777398+0100000 = 7607610
379444785 = 78658002460354141239901176718608806368 ;
786580+02460354+14123990+11767186+08806368 = 37944478
(checked all bases through 44275337)
Some other sequences are discussed here.
© 1996-2008 Robert P. Munafo.
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This work is licensed under a
Creative Commons Attribution 2.5 License.
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