#include <bits/stdc++.h>
using namespace std;
long long arr[100001];
long long arr1[100001];
int main() {
  long long n;
  cin >> n;
  vector<long long> ans;
  long long sum = 0;
  long long max1 = 0;
  for (long long i = 0; i < n; i++) {
    long long num;
    cin >> num;
    arr[i] = num;
  }
  for (long long i = 0; i < n; i++) {
    if (i == 0) {
      arr1[i] = arr[i];
    }
    arr1[i] = arr[i] - arr[i - 1];
  }
  for (long long i = 1; i <= n; i++) {
    bool status = true;
    for (long long j = 0; j < n; j++) {
      if (arr1[j] != arr1[j % i]) {
        status = false;
        break;
      }
    }
    if (!status) {
      continue;
    } else {
      ans.push_back(i);
    }
  }
  cout << ans.size() << '\n';
  for (long long i = 0; i < ans.size(); i++) {
    cout << ans[i] << " ";
  }
  return 0;
}
