1) Magic square
Found on
https://www.crosswordclues.com/clue/magic-constant
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. In general M = n(n^2 +1)/2. Harvey Heinz has a reference to a 8 x 8 magic square that Woodruff made in 1916. Each 8 cell segment of the Peano space fillin...
Found on
http://en.wikipedia.org/wiki/Magic_constant
No exact match found.
