// #pragma GCC optimize("unroll-loops", "omit-frame-pointer", "inline") // #pragma GCC option("arch=native", "tune=native", "no-zero-upper") // #pragma GCC // target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native") // #pragma GCC optimize("Ofast") // #pragma GCC optimize("tree-vectorize","openmp","predictive-commoning") // #pragma GCC option("D_GLIBCXX_PARALLEL","openmp") #include using namespace std; typedef long long ll; typedef pair P; typedef vector vi; typedef vector vll; // #define int long long #define pb push_back #define mp make_pair #define eps 1e-9 #define INF 2000000000 // 2e9 #define LLINF 2000000000000000000ll // 2e18 (llmax:9e18) #define fi first #define sec second #define all(x) (x).begin(), (x).end() #define sq(x) ((x) * (x)) #define dmp(x) cerr << #x << ": " << x << endl; template void chmin(T &a, const T &b) { if (a > b) a = b; } template void chmax(T &a, const T &b) { if (a < b) a = b; } template using MaxHeap = priority_queue; template using MinHeap = priority_queue, greater>; template vector vect(int len, T elem) { return vector(len, elem); } template ostream &operator<<(ostream &os, const pair &p) { os << p.fi << ',' << p.sec; return os; } template istream &operator>>(istream &is, pair &p) { is >> p.fi >> p.sec; return is; } template ostream &operator<<(ostream &os, const vector &vec) { for (int i = 0; i < vec.size(); i++) { os << vec[i]; if (i + 1 < vec.size()) os << ' '; } return os; } template istream &operator>>(istream &is, vector &vec) { for (int i = 0; i < vec.size(); i++) is >> vec[i]; return is; } void fastio() { cin.tie(0); ios::sync_with_stdio(0); cout << fixed << setprecision(20); } #define endl "\n" // p[i] : minimum divisor of i // x is prime <=> p[x] == x vector eratos(int N) { vector p(N + 1); p[0] = p[1] = 1; for (int i = 2; i <= N; i++) p[i] = i; for (int i = 2; i * i <= N; i++) { if (p[i] != i) continue; for (int j = i * 2; j <= N; j += i) { if (p[j] == j) p[j] = i; } } return p; } void solve() { int n; cin >> n; if (n == 1) { cout << 1 << endl; return; } auto a = eratos(200000); vector p; for (int i = 100000; i < 200000; i++) { if (p.size() > 20) break; if (a[i] == i) p.push_back(i); } vector cand; for (int i = 0; i < p.size(); i++) { for (int j = 0; j < p.size(); j++) { cand.push_back(p[i] * p[j]); } } sort(all(cand)); cand.erase(unique(all(cand)), cand.end()); cout << cand[n - 2] << endl; return; } signed main() { fastio(); solve(); // int t; cin >> t; while(t--)solve(); // int t; cin >> t; // for(int i=1;i<=t;i++){ // cout << "Case #" << i << ": "; // solve(); // } return 0; }