Explanation 13x13 magic square
The 13x13 magic square is odd and a prime number. To construct a 13x13 magic square use the same methods to construct a 5x5, 7x7 and 11x11 magic square. Most perfect magic 13x13 square is panmagic and symmetric.
For more detailed explanation see the 5x5 magic square.
The methods to construct an 13x13 magic square are:
With the first five methods you can construct simple, symmetric 13x13 magic squares.
Use the shift method to construct panmagic 13x13 squares.
The ultra magic 13x13 square is panmagic and symmetric.
Concentric [with diamond] and pan 11x11 in 13x13 are specials.