What’s the same and what’s different about the following sums?

\(\displaystyle\sum_{r=0}^{n} r^2\)

\(\displaystyle\sum_{r=1}^{n} r^2\)

\(\displaystyle\sum_{r=0}^{n-1} (r+1)^2\)

What’s the same and what’s different about the following sums?

\(\displaystyle\sum_{r=0}^{n} r^2\)

\(\displaystyle\sum_{r=1}^{n} r^2\)

\(\displaystyle\sum_{r=0}^{n-1} (r+1)^2\)