typedef long long ll;
typedef long double ld;
#include <bits/stdc++.h>
using namespace std;
#define int long long

struct Eratos {
    vector<int> primes;
    vector<bool> isprime;
    vector<int> mebius;
    vector<int> min_factor;

    Eratos(int MAX) : primes(),
                      isprime(MAX+1, true),
                      mebius(MAX+1, 1),
                      min_factor(MAX+1, -1) {
        isprime[0] = isprime[1] = false;
        min_factor[0] = 0, min_factor[1] = 1;
        for (int i = 2; i <= MAX; ++i) {
            if (!isprime[i]) continue;
            primes.push_back(i);
            mebius[i] = -1;
            min_factor[i] = i;
            for (int j = i*2; j <= MAX; j += i) {
                isprime[j] = false;
                if ((j / i) % i == 0) mebius[j] = 0;
                else mebius[j] = -mebius[j];
                if (min_factor[j] == -1) min_factor[j] = i;
            }
        }
    }

    // prime factorization
    vector<pair<int,int>> prime_factors(int n) {
        vector<pair<int,int> > res;
        while (n != 1) {
            int prime = min_factor[n];
            int exp = 0;
            while (min_factor[n] == prime) {
                ++exp;
                n /= prime;
            }
            res.push_back(make_pair(prime, exp));
        }
        return res;
    }

    // enumerate divisors
    vector<int> divisors(int n) {
        vector<int> res({1});
        auto pf = prime_factors(n);
        for (auto p : pf) {
            int n = (int)res.size();
            for (int i = 0; i < n; ++i) {
                int v = 1;
                for (int j = 0; j < p.second; ++j) {
                    v *= p.first;
                    res.push_back(res[i] * v);
                }
            }
        }
        return res;
    }
};


const int MAX = 210000;

signed main(){
    Eratos er(MAX);
    vector<vector<int>> divs(MAX);
    for (int n = 1; n < MAX; ++n) divs[n] = er.divisors(n);
    ll n,m;
    std::cin >> n>>m;
    vector<bool> idea(n+1),real(n+1);
    for (int i = 1; i <= n; i++) {
        for (auto e : divs[i]) {
            idea[e] = !idea[e];
        }
    }
    for (int i = 0; i < m; i++) {
        ll a;
        std::cin >> a;
        real[a]=true;
    }
    ll cnt = 0;
    for (int i = n; i >= 1; i--) {
        if(idea[i]!=real[i]){
            cnt++;
            for (auto e : divs[i]) {
                real[e] = !real[e];
            }
        }
    }
    std::cout << cnt << std::endl;
}