If we look at the center of the odd sized squares in Agrippa’s magic squares (Saturn, Mars, Mercury, Moon), we can spot lengths of the sides of right triangles. By extension, this holds for all odd sized squares built in the same way.
After the trigram squares, looking for a further transformation of the LuoShu, we can relax the constraint on the sum of the diagonals. This gives us 64 extra squares that could be mapped on the 64 hexagrams of the I Ching.
The Luoshu layout follows the traditional convention of chinese maps, where North is at the bottom and South at the top, so number one is drawn at the bottom center and number nine at the top center. Still, this is not the only possible layout for a 3×3 magic square and we can take avantage of this to make a link to another chinese concept, the trigrams.
We can use the trigrams as binary encoding of the three transformations: rotation, horizontal mirroring and vertical mirroring. Thus assigning each one of the eight trigrams to one of the eight 3×3 magic squares.
While the LuoShu (3×3 magic square) is simple to memorize by itself, one visual trick to remember the layout of the nine numbers is the Taijitu (yin-yang symbol). Write down the numbers from one to nine following the swirling pattern then exchange two and eight.
One to four belong to the shadow, while six to nine are on the sunny side.