#include <stdio.h>
#include <stdlib.h>

int main()
{
    FILE *f = fopen("twoton.in","rt");
    int n,x,mini=200000,minpos=-1;
    fscanf(f,"%d",&n);
    for (int i=0;i<n;++i){
        fscanf(f,"%d",&x);
        if (mini>x){
            mini=x;
            minpos=i;
        }
    }
    fclose(f);
    f = fopen("twoton.out","wt");
    fprintf(f,"%d",(1UL<<n) - (1UL<<(n-minpos-1)));
    fclose(f);
    return 0;
}