#include <bits/stdc++.h>

using namespace std;
using ll = long long;

int main(){

    ll N, M, c, ans=0;
    cin >> N >> M;

    vector<ll> cnt(N+1), open(N+1);
    vector<vector<ll>> div(N+1);

    for (int i=1; i<=N; i++){
        for (int j=i; j<=N; j+=i) div[j].push_back(i);
    }

    for (int i=1; i<=M; i++){
        cin >> c;
        open[c] = 1;
    }

    for (int i=N; i>=1; i--){
        if (open[i] != (cnt[i]+1) % 2) ans++;
        else for (auto x : div[i]) cnt[x]++;
    }

    cout << ans << endl;

    return 0;
}