[mini]

#include <cstdlib>
#include <iostream>

using namespace std;

int N;

long A(int n)
{
 return (N-n);
}

int main(int argc, char *argv[])
{
    int n;
    long sum=0;
    
    printf("請輸入階層數：");
    cin >> N;
    for(n=1; n<=N; n++){
      cout << n << "*[1*(N-" << n-1 << ")]";
      sum=sum+(n*A(n-1));
      if(n<N){
        cout << " + ";
      }else{
        cout << "=" << sum << '\n';
      }
    }
    
    system("PAUSE");
    return EXIT_SUCCESS;
}

以上當然可以簡化