Magic constant
Appearance
The magic constant or magic sum of a magic square is the sum of numbers in any row, column, or diagonal of the magic square. For example, the magic square shown below has a magic constant of 15.

The term magic constant or magic sum is similarly applied to other "magic" figures such as magic stars and magic cubes.
Magic stars
The magic constant of an n-pointed normal magic star is M = 4n + 2.