Magic Square of Cubes Solutions

4x4 Magic Square of Cubes of Distinct Integers
4x4 Semi-Magic Squares of Cubes of Distinct Positive Integers
5x5 Magic Square of Distinct Cubes
5x5 Semi-Magic Squares of Distinct Positive Cubes
6x6 Magic Square of Distinct Cubes
7x7 Magic Square of Distinct Cubes
8x8 Semi-Magic Square of Distinct Positive Cubes


4x4 Magic Square of Cubes of Distinct Integers
All of the known 4x4 magic squares of cubes use the following structure
or its transpose.

 A3  B3  C3  D3
 E3  F3  G3  H3
-E3 -F3 -G3 -H3
-A3 -B3 -C3 -D3

This is the smallest solution.
 193  -33 -103 -183
-423  213  283  353
 423 -213 -283 -353
-193   33  103  183

It is an open problem whether there exists a 4x4 magic square of cubes
of distinct positive integers.  It is also an open problem whether there
is a solution with any distinct integers not having the above structure.

There is a related problem which provably has this same kind of solution set.
It is three cubes in arithmetic progression: x3 + y3 = 2z3.
There is no solution in distinct positive integers
and the only solutions allowing negative integers have z = 0 and x = -y.
Can the method of proof used by the three cubes problem be used to prove
that the 4x4 magic square of cubes problem must have the above structure?



4x4 Semi-Magic Squares of Cubes of Distinct Positive Integers
Seven of the eight smallest solutions use the following structure.
     (af)3 (de)3 (ce)3 (bf)3,
     (bh)3 (cg)3 (dg)3 (ah)3,
     (bg)3 (ch)3 (dh)3 (ag)3,
     (ae)3 (df)3 (cf)3 (be)3,
where
     a3 + b3 = c3 + d3 = p,
     e3 + f3 = g3 + h3 = q.
with magic sum = pq.

(MaxNb = 192, S3 = 7,095,816 = 1729 x 4104)
 243 1443   23 1603
1923  183  163  203
 153  903 1803  813
  93 1503 1083 1353

(MaxNb = 313, S3 = 42,699,384)
3133  953 1273 2093
1353 2973  733 2393
 893 1093 2753 2713
2073 2433 2693  253

(MaxNb = 324,  S3 = 35,760,907 = 1729 x 20,683)
3243   273  1003  903
 243  2883  1713  1903
1203   103  2703  2433
 193  2283  2163  2403

(MaxNb = 408, S3 = 67,970,448 = 1729 x 39,312)
4083  333  243  153
 343 3963   23 1803
 203 1353 3403 2973
 183 1503 3063 3303

(MaxNb = 408, S3 = 69,217,057 = 1729 x 40,033)
4083  343  903  813
 333 3963 1443 1603
1083   93 3403 3063
 163 1923 2973 3303

(MaxNb = 432, S3 = 84,883,032 = 4104 x 20,683)
4323 1603  483  383
1503 4053 1713 2163
 543  203 3843 3043
 903 2433 2853 3603

(MaxNb = 468, S3 = 111,057,128 = 1729 x 64,232)
4683  393 1703 1533
 363 4323 2343 2603
2043  173 3903 3513
 263 3123 3243 3603

(MaxNb = 480, S3 = 113,643,712 = 1729 x 65,728)
4803 1443  333  313
1203 4003 2793 2973
 403  123 3963 3723
1083 3603 3103 3303



5x5 Magic Square of Distinct Cubes
The smallest solution has an associated structure.

 113 -203  123  133  143
-153  213   33 -103 -173
 -53  -43   03   43   53
 173  103  -33 -213  153
-143 -133 -123  203 -113



5x5 Semi-Magic Squares of Distinct Positive Cubes

(MaxNb=110, S3=1,408,896)
1103  103  403  233   93
  33 1013  183  483  643
 213  673  983   63  543
 363  143  703  973  473
 283  423  383  723  963

(MaxNb=141, S3=4,416,616)
1413  753  823  163  863
 393 1293   43  903 1143
 253  713 1283 1243  343
 263  583 1183 1163 1003
1153 1093  503  603 1083



6x6 Magic Square of Distinct Cubes
 183   33 -133  133  -33 -183
  13 -143  -83  -13  143   83
-103  173  -43   43 -173  103
-163  -53  153 -153   53  163
 -93  -73   93  -63   73   63
 -23 -123 -113 -113  123   23



7x7 Magic Square of Distinct Cubes
-173  -63 -213  203  123  193 -133
  93   73 -153  -13  103  113  -33
-183 -163   83  -53   43   63  213
 243  233  223   03 -243 -233 -223
-143 -193  133   53  173 -123  163
-103 -113  -93   13  153  -73   33
 -43  -23   23 -203  143  183  -83



8x8 Semi-Magic Square of Distinct Positive Cubes
using distinct positive integers 1...653.
(1...643 is not possible).
(magic sum = 551,979)
653  643   93  123   63  233   73   33
 23  293  633  253  453  133  513  333
203  483  193  623  173  153  523  343
283  223  383  323  613  373  413  443
103  113  603  403  273  423  303  533
433  213  263  463  243  593  163  503
 83  313  183  353  583  543  143  493
553  473   43  393   53  363  563   13