View Code of Problem 31

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<vector>
#include<map>
#include<string>
#include<set>
using namespace std;
int main(void){
	long long t;
	while(~scanf("%lld",&t)){
		long long i=1;
		for(int j=1;j<t;j++)
			i+=5;
		long long sum=(long long)i*21+2;
		printf("%lld\n",sum);
	}
}