#include<bits/stdc++.h>
using namespace std;
#include <unordered_set>
#include <random>
//#define int long long
#define REP(i,m,n) for(int i=(m);i<(n);i++)
#define rep(i,n) REP(i,0,n)
#define pb push_back
#define all(a) a.begin(),a.end()
#define rall(c) (c).rbegin(),(c).rend()
#define mp make_pair
#define endl '\n'
//#define vec vector<ll>
//#define mat vector<vector<ll> >
#define fi first
#define se second
#define double long double
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pll;
//typedef long double ld;
typedef complex<double> Complex;
const ll INF=1e9+7;
const ll MOD=998244353;
const ll inf=INF*INF;
const ll mod=INF;
const ll MAX=200010;
const double PI=acos(-1.0);
typedef vector<vector<ll> > mat;
typedef vector<ll> vec;

ll dx[]={0,1,0,-1};
ll dy[]={1,0,-1,0};

void solve(){
    ll n,m;cin>>n>>m;
    vector<ll>a(n+1);
    rep(i,m){
        ll s;cin>>s;
        a[s]=1;
    }
    vector<vector<ll> >b(n+1);
    REP(i,1,n+1){
        for(int j=1;j*j<=i;j++){
            if(j*j==i){
                b[i].pb(j);
                break;
            }
            if(i%j==0){
                b[i].pb(j);
                b[i].pb(i/j);
            }
        }
    }
    ll ans=0;
    vector<ll>c(n+1,1);
    for(int i=n;i>=1;i--){
        if(a[i]!=c[i]){
            ans++;
        }else{
            rep(j,b[i].size()){
                c[b[i][j]]=1-c[b[i][j]];
            }
        }
    }
    cout<<ans<<endl;
}

signed main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    solve();
}