#include<bits/stdc++.h>
using namespace std;
#define endl '\n'
int n = 0;
unsigned long long sum = 0;
int brr[200010] = { 0 };
int main()
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> n;
	int tp = 0, temp = 0;
	cin >> tp;
	for (int i = 1; i < n; i++)
	{
		cin >> temp;
		brr[i] = brr[i - 1];
		if (temp < tp)
		{
			int x = tp / temp;
			int y = log2(x);
			if (temp*pow(2,y) < tp)y++;
			brr[i] += y;
		}
		else if (temp > tp)
		{
			int x = temp / tp;
			int y = log2(x);
			brr[i] = max(0, brr[i] - y);
		}
		tp = temp;
	}
	for (int i = 1; i < n; i++)sum += brr[i];
	cout << sum;
}