#include <bits/stdc++.h>
#define syosu(x) fixed<<setprecision(x)
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> P;
typedef pair<double,double> pdd;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<string> vs;
typedef vector<P> vp;
typedef vector<vp> vvp;
typedef vector<pll> vpll;
typedef pair<int,P> pip;
typedef vector<pip> vip;
const int inf=1<<30;
const ll INF=1ll<<60;
const double pi=acos(-1);
const double eps=1e-8;
const ull mod=1e9+7;
const int dx[4]={-1,0,1,0},dy[4]={0,-1,0,1};

int n,m;
vi a,b;

int main(){
	cin>>n>>m;
	a=vi(n,1);
	b=vi(m);
	a[0]=a[1]=0;
	for(int i=2;i<n;i++) if(a[i]){
		for(int j=2*i;j<n;j+=i) a[j]=0;
	}
	for(int i=0;i<m;i++) cin>>b[i];
	sort(b.begin(),b.end());
	vi dp(n,-inf);
	dp[0]=0;
	for(int i=0;i<m;i++) for(int j=b[i];j<n;j++) dp[j]=max(dp[j],dp[j-b[i]]+1);
	ll res=0;
	for(int i=1;i<n;i++) if(a[i]&&dp[n-i]>0) res+=dp[n-i];
	while(n>=b[0]) n-=b[0],res++;
	cout<<res<<endl;
}