Tuesday, 21th July, 2009

Project Euler Problem 6

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) = 55^(2) = 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.

I smell a sum(), and maybe, if we’re lucky, a one liner. Lady luck was smiling this day:

(sum([x for x in range(101)])**2) - sum([x**2 for x in range(101)])

Done! :-D