For example let 2n 1 be 7 which is an odd integer. The square root of 4 4 2 so two digits were added. Sum of first three odd numbers 1 3 5 9 3 x 3.
25 are 5 columns of 5 but also 13579.
16 are 4 columns of 4. For 9 you will draw 3 columns of 3. Take some time to figure out why even better find a reason that would work on a nine-year-old. And now find the difference between consecutive squares.