링크
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.
sum (k = 1~n) k = n * (n+1) / 2
sum (k = 1~n) k^2 = n * (n+1) * (2n+1) / 6
python 1
python 2