Symmetrical magic squares

An important, relatively frequent special form of magic squares are symmetrical squares, where all pairs of cells diametrically equidistant from the center have the same sum n2 + 1. These number pairs are said to be complementary.

4619411429224
1739123472244
3710325274915
830325472042
3512345184013
6284316381133
264821369314

Symmetrical magic squares have been intensively investigated. Some important results are given here: