Explanation 19x19 magic square
The 19x19 magic square is odd and a prime number. To construct a 19x19 magic square use the same methods to construct a 5x5, 7x7, 11x11, 13x13 and 17x17 magic square. Most perfect magic 19x19 square is panmagic and symmetric.
For more detailed explanation see the 5x5 magic square.
The methods to construct an 19x19 magic square are:
With the first five methods you can construct simple, symmetric 19x19 magic squares.
Use the shift method to construct panmagic 19x19 squares.
The ultra magic 19x19 square is panmagic and symmetric.
Concentric [with diamond] and pan 17x17 in 19x19 are specials.