Magic Square
Arrange the numbers so rows, columns and diagonals share a sum.
↘ 0↙ 0
000
000
Target sum: 15
There are 8 solutions on 3×3, forming one class under rotations and reflections.
How to play
Tap a square, then tap a number on the number pad. Use each number once. Inserting a number already on the board clears its old square. Watch the row, column and diagonal sums: the target is 15 on 3×3 and 34 on 4×4. The 4×4 board is a free exploration mode.