#include <cstdio>
#include <vector>
#include <set>
#include <queue>
using std::vector;
using std::set;
using std::priority_queue;

struct Node{
	int d;
	int need;
	int t;
	bool operator < (const Node& other) const{
		return d < other.d;
	}
};

int main(){
	int n;
	scanf("%d",&n);
	vector<int> a(n);
	for(int i = 0; i < n; i++) scanf("%d",&a[i]);
	priority_queue<Node> Q;
	long long ans = 0;
	for(int i = 0; i < n; i++){
		int d = (i+1)*2;
		Q.push(Node{d, a[i]+1, 0});
		ans -= 1ll*(i+1);
	}
	set<int> have;
	for(int i = 1; i <= n; i++) have.insert(i);
	while(Q.size()!=0){
		Node cur = Q.top();
		Q.pop();
		auto find = have.lower_bound(cur.need);
		if(find == have.end()){
			if(cur.t == 0){
				Node nxt{cur.d/2, cur.need-1, 1};
				Q.push(nxt);
			}
		}
		else{
			ans += 1ll*cur.d;
			have.erase(find);
		}
	}
	printf("%lld\n",ans);
	return 0;
}