Project-Euler-with-Python/Project Euler 6.py at master · choandrew/Project-Euler-with-Python · GitHub

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"""

The 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.
"""

#two ways to do this

#brute force comp sci way
#or math way

#math way:


n = int(input("What number? "))

def sumofsquares(n):
    return n*(n+1)*(2*n+1)/6

def squareofsum(n):
    return n ** 2 * (n+1) **2 / 4

print(squareofsum(n)-sumofsquares(n))