#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int nax = 1e4 + 7;
vector<int>prime(nax, true);
void is_prime() {
	prime[0] = false;
	prime[1] = false;
	for (int i = 2; i < nax; i++) {
		if (prime[i] && ll(i * i) < nax) {
			for (int j = i * i; j * j <= nax; j += i) {
				prime[j] = false;
			}
		}
	}
}
int main() {
// #ifndef ONLINE_JUDGE
// 	freopen("input.txt", "r", stdin);
// 	freopen("output.txt", "w", stdout);
// #endif
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n, m;
	cin >> m >> n;
	is_prime();
	vector<int>v(n);
	for (int i = 0; i < n; i++) {
		cin >> v[i];
	}
	sort(v.begin(), v.end());
	vector<int>dp(nax, -1);
	dp[m] = 0;
	for (int rem = m; rem >= 0; rem--) {
		for (int rep = 0; rep < n; rep++) {
			if (rem - v[rep] >= 0) {
				dp[rem - v[rep]] = max(1 + dp[rem], dp[rem - v[rep]]);
			}
		}
	}
	int ans = 0;
	for (int i = 0; i <= m; i++) {
		if (prime[i] && dp[i] != -1) {
			ans += dp[i];
		}
	}
	cout << ans << endl;
}