#include<stdio.h>
#include<math.h>

int main(){
    FILE *in;
    in = fopen("nunta.in","r");
    FILE *out;
    out = fopen("nunta.out","w");
    
    int n;
    fscanf(in,"%d",&n);
    fprintf(out,"%ld",pow(2,n-1)-1);
    
    return 0;
}