// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

#define rep(i, n) for(int i = 0; i < (n); i++)

#define rep1(i, n) for(int i = 1; i <= (n); i++)

#define co(x) cout << (x) << "\n"

#define cosp(x) cout << (x) << " "

#define ce(x) cerr << (x) << "\n"

#define cesp(x) cerr << (x) << " "

#define pb push_back

#define mp make_pair

#define Would

#define you

#define please



int main() {

	cin.tie(0);

	ios::sync_with_stdio(false);





	int N;

	cin >> N;

	int A[200000];

	rep(i, N) cin >> A[i];



	ll B[200001], C[200001];

	B[0] = 0;

	C[N] = 0;



	vector<int> V;

	ll mae = A[0];

	V.pb(0);

	rep(i, N) {

		ll a = A[i];

		B[i + 1] = B[i];

		if (mae >= a) {

			a *= 4;

			while (mae >= a) {

				V.pb(0);

				a *= 4;

			}

			V[(int)V.size() - 1]++;

		}

		else {

			while (mae < a) {

				int kari = V[(int)V.size() - 1];

				B[i + 1] += kari;

				if (V.size() > 1) {

					V.pop_back();

					V[(int)V.size() - 1] += kari;

				}

				mae *= 4;

			}

			V[(int)V.size() - 1]++;

		}

		mae = A[i];

	}

	V.clear();

	mae = A[N - 1];

	V.pb(0);

	for (int i = N - 1; i >= 0; i--) {

		ll a = A[i];

		C[i] = C[i + 1];

		if (mae >= a) {

			a *= 4;

			while (mae >= a) {

				V.pb(0);

				a *= 4;

			}

			V[(int)V.size() - 1]++;

		}

		else {

			while (mae < a) {

				int kari = V[(int)V.size() - 1];

				C[i] += kari;

				if (V.size() > 1) {

					V.pop_back();

					V[(int)V.size() - 1] += kari;

				}

				mae *= 4;

			}

			V[(int)V.size() - 1]++;

		}

		mae = A[i];

	}



	ll kotae = 1e18;

	rep(i, N + 1) {

		kotae = min(kotae, 2 * B[i] + 2 * C[i] + i);

	}

	co(kotae);



	Would you please return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.1336019842208287x):
//#include<bits/stdc++.h>

//難しい問題解いてるなぁ

#include<cstdio>

#include<algorithm>

#include<vector>

using namespace std;

typedef long long ll;

#define rep(i, n) for(int i = 0; i < (n); i++)

#define rep1(i, n) for(int i = 1; i <= (n); i++)

#define co(x) cout << (x) << "\n"

#define cosp(x) cout << (x) << " "

#define ce(x) cerr << (x) << "\n"

#define cesp(x) cerr << (x) << " "

#define pb push_back

#define mp make_pair

#define Would

#define you

#define please



const int cm = 1 << 17;

char cn[cm], * ci = cn + cm, ct;

inline char getcha() {

	if (ci - cn == cm) { fread(cn, 1, cm, stdin); ci = cn; }

	return *ci++;

}

inline int getint() {

	int A = 0;

	if (ci - cn + 16 > cm) while ((ct = getcha()) >= '0') A = A * 10 + ct - '0';

	else while ((ct = *ci++) >= '0') A = A * 10 + ct - '0';

	return A;

}



int main() {

	//cin.tie(0);

	//ios::sync_with_stdio(false);





	int N;

	N = getint();

	int A[200000];

	ll B[200001], C;

	B[0] = 0;

	C = 0;



	vector<int> V;

	V.pb(0);

	rep(i, N) A[i] = getint();

	ll mae = A[0];

	rep(i, N) {

		ll a = A[i];

		B[i + 1] = B[i];

		if (mae >= a) {

			a *= 4;

			while (mae >= a) {

				V.pb(0);

				a *= 4;

			}

			V.back()++;

		}

		else {

			while (mae < a) {

				int kari = V.back();

				B[i + 1] += kari;

				if (V.size() > 1) {

					V.pop_back();

					V.back() += kari;

				}

				mae *= 4;

			}

			V.back()++;

		}

		mae = A[i];

	}

	V.clear();

	mae = A[N - 1];

	V.pb(0);

	ll kotae = 2 * B[N] + N;

	for (int i = N - 1; i >= 0; i--) {

		ll a = A[i];

		if (mae >= a) {

			a *= 4;

			while (mae >= a) {

				V.pb(0);

				a *= 4;

			}

			V.back()++;

		}

		else {

			while (mae < a) {

				int kari = V.back();

				C += kari;

				if (V.size() > 1) {

					V.pop_back();

					V.back() += kari;

				}

				mae *= 4;

			}

			V.back()++;

		}

		mae = A[i];

		kotae = min(kotae, B[i] + B[i] + C + C + i);

	}



	printf("%lld", kotae);



	Would you please return 0;

}