Continuing the wonderful community solutions to Project Euler.
This is Problem 6, sum square difference.
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.