#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <array>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
#include <memory>
#include <regex>
using namespace std;

void findPrime(int N, vector<bool>& isPrime)
{
    isPrime.assign(N+1, true);
    isPrime[0] = isPrime[1] = false;
    for(int i=2; i*i<=N; i++){
        if(isPrime[i]){
            for(int j=i; i*j<=N; j++){
                isPrime[i*j] = false;
            }
        }
    }
}

int main()
{
    int n;
    cin >> n;
    vector<bool> isPrime;
    findPrime(2*n, isPrime);

    int ans = 0;
    for(int r=1; r*r<=2*n; ++r){
        if(!isPrime[r])
            continue;
        for(int p=1; p<=n && p<r*r; ++p){
            int q = r * r - p;
            if(q <= n && isPrime[p] && isPrime[q])
                ++ ans;
        }
    }
    cout << ans << endl;

    return 0;
}