Python/Project Euler/Problem 06/sol2.py
2018-10-19 14:00:31 +05:30

16 lines
619 B
Python
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

# -*- coding: utf-8 -*-
'''
Problem:
The sum of the squares of the first ten natural numbers is,
1^2 + 2^2 + ... + 10^2 = 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 N natural numbers and the square of the sum.
'''
from __future__ import print_function
n = int(raw_input())
suma = n*(n+1)/2
suma **= 2
sumb = n*(n+1)*(2*n+1)/6
print(suma-sumb)