#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
#define all(A) A.begin(),A.end()
#define rep(i, n) for (ll i = 0; i < (ll) (n); i++)


bool chmax(ll& p, ll q) {
    if (p < q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}

bool chmin(ll& p, ll q) {
    if (p > q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}


int main() {
    
    ll N,M;
    cin>>N>>M;
    vll A(N+1,0);
    for(ll i=1;i<=N;i++){
        for(ll j=1;j*j<=i;j++){
            if(i%j==0){
                 A[j]=1-A[j]; 
                 if(j*j!=i){
                     A[i/j]=1-A[i/j];
                 }
            }
          
        }
    }

    vll D(N+1,0);
    rep(i,M){
        ll P;
        cin>>P;
        D[P]=1;
    }
    ll an=0;
    for(ll i=N;i>0;i--){
        if(A[i]!=D[i]){
            an++;
            for(ll j=1;j*j<=i;j++){
                if(i%j==0){
                    D[j]=1-D[j];
                    if(i!=j*j){
                        D[i/j]=1-D[i/j];
                    }
                }
            }
        }
    }
    cout<<an<<endl;
    

    

    
}