#include<iostream>

using namespace std;

int A[(1 << 18)];
bool Used[(1 << 18)];

int main(){
   int n;
   cin >> n;
   for(int i = 0; i < (1 << n); i++){
      int x;
      cin >> x;
      int pos = 0;
      int l = (1 << (n-1)),r = 1;
      for(int j = 0; j <= n/2; j++){
	 if(l & i){
	    pos |= r;
	 }
	 if(r & i){
	    pos |= l;
	 }
	 l /= 2;
	 r *= 2;
      }
      A[pos] = x;
   }
   
   int saved = 0;
   for(int i = n; i > 0; i--){
      int s = (1 << i);
      int pos = 0;
      while(pos < (1 << n)){
	 if(!Used[pos]){
	    bool works = true;
	    int cur = A[pos];
	    for(int j = pos; j < pos+s; j++){
	       if(cur != A[j]){
		  works = false;
		  break;
	       }
	    }
	    if(works){
	       for(int j = pos; j < pos+s; j++){
		  Used[j] = true;
	       }
	       saved += (1 << (i+1)) - 2;
	    }
	 }
	 pos += s;
      }
   }

   cout << (1 << (n+1)) - 1 - saved << endl;
   return 0;
}