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Problem 6

Solved on 2/26/2008

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.

Please enter a Number:

for($c = 1; $c<=$number; $c++){
$sum_of_squares += $c*$c;
}
$sum = ($number+1)*($number/2);
$square_of_sums = $sum*$sum;
$sum_of_squares:
$square_of_sums:
$difference: