# Square Pyramid Problem Involving Division of Blocks into Perfect Square Groups

"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 -

$$35n^2=\frac{(k)(k+1)(2k+1)}6$$

The integer solutions to this equation should probably render the solutions to this problem.

Please extend help to proceed further.

Thank you.