#include <stdio.h>
#include <math.h>
int main() {
int n,i,j,a[31];
a[1] = 4;
for (i=2;i<=30;i++) {
a[i] = (a[i-1] -1) * 2;
}
scanf("%d",&n);
while(n--) {
scanf("%d",&j);
printf("%d\n",a[j]);
}
return 0;
}