#include <bits/stdc++.h>

using namespace std;

typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> puu;

#define fast ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define file_in freopen("input.txt", "r", stdin);
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)x.size()
#define fi first
#define se second

template<typename T> istream& operator>>(istream& in, vector<T> &v) { for (auto &el : v) in >> el; return in; }
template<typename T> ostream& operator<<(ostream& out, vector<T> &v) { for (auto &el : v) out << el << " "; return out; }
template<typename T1, typename T2> istream& operator>>(istream& in, pair<T1, T2> &v) { in >> v.first >> v.second; return in; }
template<typename T1, typename T2> ostream& operator<<(ostream& out, pair<T1, T2> &v) { cout << v.first << " " << v.second; return out; }

int main() {
    fast
    // file_in

    int n;
    cin >> n;
    n = (1 << n);
    vector<int> a(n);
    cin >> a;
    if (n == 2) {
        cout << 2 << '\n';
        return 0;
    }
    int mask = 0, cnt = 0;
    ll res = 0;
    unordered_map<int, vector<int>> ht;
    for (int i = 0; i < n; ++i) {
        a[i] = min(a[i], n - a[i] - 1);
        if ((mask >> a[i]) & 1) ++cnt;
        mask ^= 1 << a[i];
        if (ht[mask].empty()) {
            ht[mask].resize(2);
        }
        res += ht[mask][cnt % 2];
        ht[mask][cnt % 2]++;
    }
    cout << 1ll * n * (n + 1) / 2 - res - ht[0][0] << '\n';
    return 0;
}