Sum of square of first n even numbers | Efficient C ++ method to find sum of square of first n even numbers . ; Driver code
#include <iostream> NEW_LINE using namespace std ; int squareSum ( int n ) { return 2 * n * ( n + 1 ) * ( 2 * n + 1 ) / 3 ; } int main ( ) { cout << squareSum ( 8 ) ; return 0 ; }