### Method of Strachey

First grid is a 2x2 carpet of a 3x3 magic square. Second grid is fixed. Take 1x number from first grid and add 9x number from the same cell of the second grid.

1x number                       +      9x number                     =     magic 6x6 square

 2 9 4 2 9 4 0 0 3 2 2 2 2 9 31 20 27 22 7 5 3 7 5 3 0 3 0 2 2 2 7 32 3 25 23 21 6 1 8 6 1 8 0 0 3 2 2 2 6 1 35 24 19 26 2 9 4 2 9 4 3 3 0 1 1 1 29 36 4 11 18 13 7 5 3 7 5 3 3 0 3 1 1 1 34 5 30 16 14 12 6 1 8 6 1 8 3 3 0 1 1 1 33 28 8 15 10 17

Alternative is:

1x number                                +       9x number                               =       Swap numbers

 2 9 4 2 9 4 0 0 0 2 2 2 2 9 4 20 27 22 7 5 3 7 5 3 0 0 0 2 2 2 7 5 3 25 23 21 6 1 8 6 1 8 0 0 0 2 2 2 6 1 8 24 19 26 2 9 4 2 9 4 3 3 3 1 1 1 29 36 31 11 18 13 7 5 3 7 5 3 3 3 3 1 1 1 34 32 30 16 14 12 6 1 8 6 1 8 3 3 3 1 1 1 33 28 35 15 10 17

magic 6x6 square

 29 9 4 20 27 22 7 32 3 25 23 21 33 1 8 24 19 26 2 36 31 11 18 13 34 5 30 16 14 12 6 28 35 15 10 17

Use the method of Strachey to construct magic squares of order is double odd. See 6x610x1014x1418x1822x2226x26 en 30x30

6x6, Method of Strachey.xls
Microsoft Excel werkblad 43.5 KB