#include <bits/stdc++.h>
using namespace std;
int main(){
  int N, M;
  cin >> N >> M;
  vector<int> A(M);
  for (int i = 0; i < M; i++){
    cin >> A[i];
  }
  vector<bool> c(N + 1, true);
  for (int i = 0; i < M; i++){
    c[A[i]] = false;
  }
  vector<vector<int>> f(N + 1);
  for (int i = 1; i <= N; i++){
    for (int j = i; j <= N; j += i){
      f[j].push_back(i);
    }
  }
  int ans  = 0;
  for (int i = N; i > 0; i--){
    if (c[i]){
      ans++;
    } else {
      for (int j : f[i]){
        c[j] = !c[j];
      }
    }
  }
  cout << ans << endl;
}