#include <bits/stdc++.h>
using std::max;
using std::min;
const int N = 100000;
int n, a[N], length[N][3];
int solve(int i, int j) {
  if (a[i] == 0 && a[j] != 0) {
    return INT_MIN;
  }
  int &ret = length[i][j - i];
  if (ret == -1) {
    ret = 2;
    for (int k = j + 1; k < n && k < j + 3; ++k) {
      if (a[i] * a[k] == a[j] * a[j]) {
        ret = max(ret, solve(j, k) + 1);
      }
    }
  }
  return ret;
}
int work() {
  memset(length, -1, sizeof(length));
  int maximum = 1;
  for (int i = 0; i < n; ++i) {
    for (int j = i + 1; j < n && j < i + 3; ++j) {
      maximum = max(maximum, solve(i, j));
    }
  }
  return min(n - maximum, 2);
}
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) {
    scanf("%d", a + i);
  }
  printf("%d\n", work());
  return 0;
}
