Project Euler: #6 - Sum square difference

Problem The sum of the squares of the first ten natural numbers is, $$1^2 + 2^2 + 3^2 + 4^2 + 5^2 + 6^2 + 7^2 + 8^2 + 9^2 + 10^2 = 385$$ The square of the sum of the first ten natural numbers is, $$(1+2+3+4+5+6+7+8+9+10)^2 = 55^2 = 3025$$ Hence the d...