
#include <iostream>
using namespace std;
int main() {
int num;
cin >> num;
int n = 0;
int sum = 1;
while(n < num){
sum += (2*n);
n++;
}
while(num --){
cout << sum << "+";
sum += 2;
if(num == 1){
num--;
cout << sum;
}
}
}
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