Sum square difference

简单：

e sum of the squares of the first ten natural numbers is,

1² + 2² + ... + 10² = 385

The square of the sum of the first ten natural numbers is,

(1 + 2 + ... + 10)² = 55² = 3025

Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is 3025 385 = 2640.

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

def naturalnumber(n):
    sumnatural = 0
    for i in xrange(1,n+1):
        sumnatural += i * i
    return sumnatural

def squarenumber(n):
    sumsquare = 0
    for i in xrange(1,n+1):
        sumsquare += i
    return sumsquare * sumsquare

print squarenumber(100) - naturalnumber(100)

C:\webpy\webpy\Scripts\python.exe C:/pycode/euler.py
25164150

Process finished with exit code 0