"Using 140 stone blocks, a square pyramid whose base has 7 blocks on each side can be made. At the same time, these blocks can be arranged into 35 perfect 2*2 squares. Find other positive integer values of n for which 35 perfect n*n squares can also be arranged into a square pyramid."
I arrived at this fairly obvious equation -
The integer solutions to this equation should probably render the solutions to this problem.
Please extend help to proceed further.