How many squares would there be in total on chess board

204.
it is       8 squared+ 7 squared+ 6 squared+………..+1

Let’s generalize a formula for mxn chess board( given n<m).

So total no. of elements in the chess board would be squares.
So, m*n.
Then we will select 2*2 squares, which will be (m-1)*(n-1).
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On further repeating , we will get that:
Total no. of squares= Σ(i=0 to i=n-1) (m-i)*(n-i)

There are 64 squares of 1×1
There are 49 squares of 2×2
There are 36 squares of 3×3
There are 25 squares of 4×4
There are 16 squares of 5×5
There are 09 squares of 6×6
There are 04 squares of 7×7
There is     01 square   of 8×8
Total =204 squares