#include <iostream>
using namespace std;

int main() {
    int num;
    cin >> num;
    int num1 = num;
    int num2 = num * num;
    num = num * num * num;
    int i = num2 - num1 + 1;
    do{
        num = num - i;
        if(num == 0){
            cout << i << endl;
        }
        else{
            cout << i << "+";
        }
        i+=2;
    }while(num!= 0);
}

稍微观察一下规律,发现这个奇数一定是平方减去自身再加一开始算的,这样的就好计算了