#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
template <class T, class F>
T binarySearch(T ok, T ng, const F &f) {
	while (abs(ok - ng) > 1) {
		T mid = (ok + ng) / 2;
		(f(mid) ? ok : ng) = mid;
	}
	return ok;
}
int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int n; cin >> n;
	vector<int>cnt(5001);
	rep(i, n) {
		int a; cin >> a;
		cnt[a]++;
	}
	auto f = [&](const int x)->bool {
		int st = 5000 + x;
		int ed = st + 1;
		mf_graph<int>g(ed + 1);
		rep(i, x) g.add_edge(st, i, 1);
		rep(i, 5000) g.add_edge(x + i, ed, cnt[i + 1]);
		rep(i, x)rep(j, 5000) {
			int i2 = i + 1;
			int j2 = j + 1;
			if (j2%i2)continue;
			int p = i;
			int q = x + j;
			g.add_edge(p, q, 1);
		}
		auto f = g.flow(st, ed);
		return f == x;
	};
	auto ans = binarySearch(0, 5001, f);
	cout << ans << endl;
	return 0;
}