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42000 - 42999

42021

420212 = 883 + 893 + 903 + 913 + 923 + ... + 2903.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42025

42025 = (43 + 23 + 03 + 23 + 53)2.

42025 = 2052, and 4 = 22, 2025 = 452.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42028

420282 = (42 + 3)(472 + 3)(2052 + 3).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42054

420542 = (162 + 2)(182 + 2)(1452 + 2).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42063

420632± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42066

420662 = (12 + 2)(42 + 2)(62 + 2)(132 + 2)(712 + 2) = (22 + 2)(52 + 2)(112 + 2)(2982 + 2).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42070

420702 = 85762 + 85772 + 85782 + 85792 + ... + 85992.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42150

421502 = (12 + 9)(133292 + 9).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42166

421662 = 1777971556, a square with odd digits except the last digit 6.

Page of Squares : First Upload August 31, 2013 ; Last Revised August 31, 2013
by Yoshio Mimura, Kobe, Japan

42182

421822± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42183

421832 = (342 + 5)(12382 + 5).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42194

421942 = (122 + 2)(34922 + 2).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42210

422102 = (52 + 5)(102 + 5)(142 + 5)(532 + 5).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42240

422402 = (32 - 1)(72 - 1)(92 - 1)(2412 - 1) = (32 - 1)(112 - 1)(212 - 1)(652 - 1)
= (32 - 1)(212 - 1)(232 - 1)(312 - 1) = (212 - 1)(312 - 1)(652 - 1).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42250

422502 = (52 + 1)(82 + 1)(182 + 1)(572 + 1)
= (12 + 4)(32 + 4)(112 + 4)(162 + 4)(292 + 4) = (32 + 4)(112 + 4)(292 + 4)(362 + 4).

Page of Squares : First Upload November 9, 2013 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42276

422762 = (32 + 3)(572 + 3)(2142 + 3).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42327

423272± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42336

2102 + 42336 = 2942, 2102 - 42336 = 422.

423362 = (82 - 1)(552 - 1)(972 - 1).

Page of Squares : First Upload July 28, 2012 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42340

423402± 3 are primes.

423402 = (42 + 4)(52 + 4)(192 + 4)(922 + 4) = (192 + 4)(242 + 4)(922 + 4).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42348

423482± 5 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42350

423502 = (12 + 6)(22 + 6)(42 + 6)(292 + 6)(372 + 6) = (12 + 6)(42 + 6)(372 + 6)(922 + 6)
= (22 + 6)(42 + 6)(72 + 6)(132 + 6)(292 + 6) = (22 + 6)(72 + 6)(292 + 6)(622 + 6)
= (42 + 6)(72 + 6)(132 + 6)(922 + 6) = (42 + 6)(82 + 6)(292 + 6)(372 + 6)
= (72 + 6)(622 + 6)(922 + 6).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42372

373 + 42372 = 3052, 373 - 42372 = 912.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42420

424202= 1106 x 1107 + 1107 x 1108 + 1108 x 1109 + 1109 x 1110 + ... + 1889 x 1890.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42421

(424212 + 9) = (22 + 9)(42 + 9)(82 + 9)(142 + 9)(192 + 9).

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42424

424242 = 1799795776, a square with odd digits except the last digit 6.

Page of Squares : First Upload August 31, 2013 ; Last Revised August 31, 2013
by Yoshio Mimura, Kobe, Japan

42426

424262± 5 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42429

424292± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42436

42436 = 2062, a zigzag square.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42458

424582± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42483

424832± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42500

425002 = (12 + 9)(52 + 9)(292 + 9)(792 + 9).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42504

4852 + 42504 = 5272, 4852 - 42504 = 4392.

425042 = (222 - 1)(432 - 1)(452 - 1).

Page of Squares : First Upload July 28, 2012 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42510

425102 = (22 + 9)(92 + 9)(102 + 9)(1192 + 9) = (22 + 9)(102 + 9)(112 + 9)(992 + 9)
= (22 + 9)(992 + 9)(1192 + 9) = (102 + 9)(412 + 9)(992 + 9).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42519

425192± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42524

425242± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42525

425252 = (22 - 1)(42 - 1)(262 - 1)(2442 - 1).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42532

425322 = (22 + 3)(52 + 3)(372 + 3)(822 + 3).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42536

425362± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42537

425372± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42596

425962± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42630

426302 = (12 + 6)(22 + 6)(92 + 6)(202 + 6)(272 + 6) = (12 + 6)(32 + 6)(92 + 6)(202 + 6)(222 + 6)
= (12 + 6)(62 + 6)(92 + 6)(132 + 6)(202 + 6) = (12 + 6)(92 + 6)(222 + 6)(782 + 6)
= (22 + 6)(62 + 6)(92 + 6)(2232 + 6) = (82 + 6)(92 + 6)(202 + 6)(272 + 6)
= (92 + 6)(382 + 6)(1202 + 6) = (202 + 6)(272 + 6)(782 + 6).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42636

426362 = (32 + 8)(52 + 8)(142 + 8)(1262 + 8) = (32 + 8)(62 + 8)(312 + 8)(502 + 8)
= (32 + 8)(822 + 8)(1262 + 8).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42640

426402 = (12 + 4)(22 + 4)(32 + 4)(42 + 4)(182 + 4)(232 + 4)
= (12 + 4)(22 + 4)(162 + 4)(182 + 4)(232 + 4) = (12 + 4)(42 + 4)(102 + 4)(182 + 4)(232 + 4)
= (22 + 4)(42 + 4)(232 + 4)(1462 + 4) = (22 + 4)(102 + 4)(232 + 4)(642 + 4)
= (22 + 4)(182 + 4)(232 + 4)(362 + 4) = (32 + 4)(42 + 4)(62 + 4)(182 + 4)(232 + 4)
= (32 + 4)(42 + 4)(182 + 4)(1462 + 4) = (32 + 4)(102 + 4)(182 + 4)(642 + 4)
= (62 + 4)(162 + 4)(182 + 4)(232 + 4) = (162 + 4)(182 + 4)(1462 + 4).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42642

426422± 5 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42645

426452± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42650

426502± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42688

426882 = (12 + 7)(42 + 7)(31472 + 7) = (12 + 7)(42 + 7)(432 + 7)(732 + 7)
= (152 + 7)(432 + 7)(652 + 7).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42700

427002± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42728

427282± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42744

427442 = 1827049536, a square with different digits.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42747

427472± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42756

427562± 5 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42768

427682 = (12 + 8)(22 + 8)(42 + 8)(52 + 8)(82 + 8)(172 + 8)
= (12 + 8)(22 + 8)(52 + 8)(162 + 8)(442 + 8) = (12 + 8)(22 + 8)(82 + 8)(172 + 8)(282 + 8)
= (12 + 8)(42 + 8)(102 + 8)(162 + 8)(172 + 8) = (12 + 8)(42 + 8)(102 + 8)(2802 + 8)
= (12 + 8)(52 + 8)(62 + 8)(82 + 8)(442 + 8) = (12 + 8)(52 + 8)(82 + 8)(102 + 8)(282 + 8)
= (12 + 8)(82 + 8)(382 + 8)(442 + 8) = (22 + 8)(162 + 8)(172 + 8)(442 + 8)
= (22 + 8)(442 + 8)(2802 + 8) = (42 + 8)(52 + 8)(82 + 8)(102 + 8)(172 + 8)
= (52 + 8)(102 + 8)(162 + 8)(442 + 8) = (62 + 8)(82 + 8)(172 + 8)(442 + 8)
= (82 + 8)(102 + 8)(172 + 8)(282 + 8).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42807

428072± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42840

6132 + 42840 = 6472, 6132 - 42840 = 5772.

428402 = (22 - 1)(32 - 1)(82 - 1)(162 - 1)(692 - 1) = (22 - 1)(32 - 1)(112 - 1)(162 - 1)(502 - 1)
= (22 - 1)(52 - 1)(502 - 1)(1012 - 1) = (22 - 1)(62 - 1)(82 - 1)(162 - 1)(332 - 1)
= (22 - 1)(162 - 1)(312 - 1)(502 - 1) = (32 - 1)(42 - 1)(52 - 1)(162 - 1)(502 - 1)
= (32 - 1)(162 - 1)(192 - 1)(502 - 1) = (52 - 1)(82 - 1)(162 - 1)(692 - 1)
= (52 - 1)(112 - 1)(162 - 1)(502 - 1) = (62 - 1)(132 - 1)(162 - 1)(352 - 1)
= (262 - 1)(332 - 1)(502 - 1).

Page of Squares : First Upload July 28, 2012 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42849

42849 = 2072, a zigzag square.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42874

428742± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42918

429182 = 22772 + 22782 + 22792 + 22802 + ... + 25872.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42920

429202 = (12 + 4)(822 + 4)(2342 + 4) = (52 + 4)(342 + 4)(2342 + 4).

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42945

429452± 2 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan

42950

429502= 1396 x 1397 + 1397 x 1398 + 1398 x 1399 + 1399 x 1400 + ... + 2020 x 2021.

Page of Squares : First Upload July 28, 2012 ; Last Revised July 28, 2012
by Yoshio Mimura, Kobe, Japan

42971

429712 = 35 + 495 + 695.

Page of Squares : First Upload September 18, 2013 ; Last Revised September 18, 2013
by Yoshio Mimura, Kobe, Japan

42988

429882± 3 are primes.

Page of Squares : First Upload March 5, 2014 ; Last Revised March 5, 2014
by Yoshio Mimura, Kobe, Japan