#include #include typedef long long int ll; #define FOR(i,a,b) for(ll i=(a);i<(b);i++) #define REP(i,n) for(ll i=0;i P; struct edge { ll to, cost; }; #define VMAX 100000 template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } ll ans=0; bool F=false; // Nafmo template 2022.09.04 // Generated by 2.12.0 https://github.com/kyuridenamida/atcoder-tools template struct PrimeSieve { int n, half; std::vector sieve; std::vector prime_list; // sieve[i] ... 2 * i + 1 PrimeSieve(T _n) : n(_n) { init(); } void init() { if (n < 2) { return; } half = (n + 1) / 2; sieve.assign(half, true); sieve[0] = false; prime_list.emplace_back(2); for (long long i = 1; 2 * i + 1 <= n; ++i) { if (!sieve[i]) continue; T p = 2 * i + 1; prime_list.emplace_back(p); for (long long j = 2 * i * (i + 1); j < half; j += p) { sieve[j] = false; } } } bool isPrime(T x) { if (x == 2) return true; if (x % 2 == 0) return false; return sieve[x / 2]; } T getPrimeCount() { return prime_list.size(); } T getKthPrime(int k) { return prime_list[k]; } }; int main(){ ll N; cin >> N; PrimeSieve ps(100000); for(auto x: ps.prime_list){ ll x2 = x * x; while(x2 <= N){ ans += x2; x2 *= x; } } cout << ans << endl; return 0; }