H : W : D
9 + 4 + 2 = 15
1 + 5 = 6
6 + 9 = 15
6 × 9 = 54
5 + 4 = 9
9 × 4 = 36
3 + 6 = 9
9 × 2 = 18
1 + 8 = 9 […]