Question 11118
Sum of the first n counting digits = n(n+1)/2
So for first 500 = 500x501/2 = 250 x 501 = 125250

Sum of first n odd numbers = n^2
Check:
Sum of first 3 odd numbers = 1+3+5 = 9
n^2 = 3^2 = 9  Yay!!