Python solution of Project Euler, problem 6

Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum.

I don't have much to say about this solution. I found this one pretty trivial to implement with Python.  I'm posting my solution just to keep everything in sequence. :)  Basically, the question is asking to find x, where

x = (1 + 2 + .. + 100)² - (1² + 1² + ... + 100²)

def main():
  N = 100
  sum1, sum2 = 0, 0
  for i in range(1, N + 1):
    sum1 += i
    sum2 += pow(i,2)
  return pow(sum1,2) - sum2

if '__main__' == __name__:
  print main()

Edit: the iterative solution was trivial, but the mathematical solution is much more efficient and clever:

Mathematical Solution (credit to Lov Loothra)

N = 100
s1 = N*(N + 1)/2 # sum of first N numbers
s2 = N*(N + 1)*(2*N + 1)/6 # sum of first N squares
print s1*s1 - s2