The object of the game is to fill in the top row with digits from 1 to 9
such that no 0s appear in the entire triangle.
Each number below the first row changes by taking
the absolute value difference of the two numbers above it.
The upper right hand number is calculated automatically, so you only need to enter the remaining 8 digits.
Please note that the two 3s in the triangle are already inserted for you and as such, cannot be changed.
There is only one solution to this puzzle, and it can be found using logic rather than trial and error.