#include <bits/stdc++.h>
using namespace std;
template <class T>
ostream& operator<<(ostream& os, const vector<T>& v) {
  for (T i : v) os << i << ' ';
  return os;
}
template <class T>
ostream& operator<<(ostream& os, const set<T>& v) {
  for (T i : v) os << i << ' ';
  return os;
}
template <class T, class S>
ostream& operator<<(ostream& os, const pair<T, S>& v) {
  os << v.first << ' ' << v.second;
  return os;
}
template <class T, class S>
ostream& operator<<(ostream& os, const unordered_map<T, S>& v) {
  for (auto i : v) os << '(' << i.first << "=>" << i.second << ')' << ' ';
  return os;
}
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target( \
    "avx2,sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
void fast() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
}
clock_t time_p = clock();
void starboy1299() {
  time_p = clock() - time_p;
  cerr << "Time Taken : " << (float)(time_p) / CLOCKS_PER_SEC << "\n";
}
const long long N = 1e5 + 5;
vector<long long> adj[N];
void solve() {
  long long n;
  cin >> n;
  vector<long long> v(n);
  for (long long i = 0; i < n; i++) cin >> v[i];
  if (is_sorted(v.begin(), v.end())) {
    cout << n << '\n';
    return;
  }
  long long curr = n;
  while (curr > 1) {
    curr = curr / 2;
    long long cnt = n / curr;
    long long idx = 0;
    for (long long i = 0; i < cnt; i++) {
      if (is_sorted(v.begin() + idx, v.begin() + idx + curr)) {
        cout << curr << '\n';
        return;
      }
      idx += curr;
    }
  }
  cout << 1 << '\n';
}
int32_t main() {
  fast();
  long long t = 1;
  while (t--) {
    solve();
  }
  starboy1299();
}
