#include <bits/stdc++.h>
using namespace std;
#define int long long
vector<int> Yakusuu(int N){
  vector<int> A={};
  for(int i=1;i*i<=N;i++)if(N%i == 0) A.push_back(i);
  int s = A.size();
  for(int i=s-1;i>=0;i--){
    if(A[i]*A[i] == N) continue;
    A.push_back(N/A[i]);
  }
  return A;
}
signed main(){
  int N,M;
  cin>>N>>M;
  vector<int> A(N,0);
  for(int i=1;i<=N;i++){
    A[i-1] = (N/i)%2;
  }
  vector<int> S(N,0);
  for(int i=0;i<M;i++){
    int a;
    cin>>a;
    S[a-1] = 1;
  }
  int ans = 0;
  for(int i=N;i>=1;i--){
    if(A[i-1] != S[i-1]){
      ans++;
      vector<int> x=Yakusuu(i);
      for(int j=0;j<x.size();j++)A[x[j]-1]=1-A[x[j]-1];
    }
  }
  cout<<ans<<endl;
}