In the lecture “*Find Expected Value of the Error*”, I feel S(n-1)^2 value shown is incorrect.

The summation should be (i=1 to n-1) instead of (i=1 to n) so,

S(n-1)^2 not equal to (n / (n-1))*Sn^2.

Please let me know if my conjecture is correct or wrong with explanation.