#include<stdio.h>
int eat(int a)
{
if(a==1)
return 1;
return (eat(a-1)+1)*2;
}
int main()
{
int n;
while(scanf("%d",&n)!=EOF)
{
printf("%d\n",eat(n));
}
return 0;
}
int eat(int a)
{
if(a==1)
return 1;
return (eat(a-1)+1)*2;
}
int main()
{
int n;
while(scanf("%d",&n)!=EOF)
{
printf("%d\n",eat(n));
}
return 0;
}