Suppose you put the numbers $1,2,\cdots ,10$ in each of the boxes below
such that every connected row and column sum to the same number. How many distinct solutions are there? (By distinct we mean disregarding cyclic permutations, reflections, etc.)
I tried this problem and found only one solution, namely $4,5, 1,10,8,2,3,6,9,7$ when read clockwise starting on the top leftmost square. I tried to prove it's unique but failed (miserably).
From experience, I know algebra isn't the best way to approach these types of problems, due to the number of variables and the symmetry of the equations. When trying to find $3\times3$ magic squares, for example, it'd be best to brute force all the possibilities rather than trying to solve a $9$-variable system.
So does anyone know how to solve this (preferably without guess-and-check)? Any help is welcomed and appreciated.