#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,a,b,c,d,e,f,g;
	cin>>n;
	a=(n+2)*2;
	b=(a+2)*2;
	c=(b+2)*2;
	d=(c+2)*2;
	e=(d+2)*2;
	f=(e+2)*2;
	cout<<f;
    return 0;
}
/**************************************************************
	Problem: 1688
	User: linyuhang
	Language: C++
	Result: Accepted
	Time:4 ms
	Memory:2072 kb
****************************************************************/