#include <bits/stdc++.h>
using namespace std;

#define REP(i, n) for (int i = (int)(0); i < (int)(n); ++i)
#define REPS(i, n) for (int i = (int)(1); i <= (int)(n); ++i)
#define RREP(i, n) for (int i = ((int)(n)-1); i >= 0; i--)
#define RREPS(i, n) for (int i = ((int)(n)); i > 0; i--)
#define IREP(i, m, n) for (int i = (int)(m); i < (int)(n); ++i)
#define IREPS(i, m, n) for (int i = (int)(m); i <= (int)(n); ++i)
#define FOR(e, c) for (auto &e : c)
#define SORT(v, n) sort(v, v + n);
#define VSORT(v) sort(v.begin(), v.end());
#define RVISORT(v) sort(v.begin(), v.end(), greater<int>());
#define ALL(v) v.begin(), v.end()

using VI = vector<int>;
using VVI = vector<VI>;
using PII = pair<int, int>;
using ll = long long;

typedef long long ll;

template<class T, class C> void chmax(T& a, C b){ a>b?:a=b; }
template<class T, class C> void chmin(T& a, C b){ a<b?:a=b; }

const ll mod=1e9+7;

bool IsPrime(int num)
{
    if (num < 2) return false;
    else if (num == 2) return true;
    else if (num % 2 == 0) return false;

    double sqrtNum = sqrt(num);
    for (int i = 3; i <= sqrtNum; i += 2)
    {
        if (num % i == 0)
        {
            return false;
        }
    }

    return true;
}

int main()
{
    cin.tie( 0 );
    ios::sync_with_stdio( false );
	
	int n;
	cin>>n;

	VI v;
	for(int i=2;i<=n;i++){
		if(IsPrime(i))v.push_back(i);
	}

	// REP(i,v.size())cout<<v[i]<<endl;
	int ans=0;
	REP(i,v.size()){
		int r=v[i]*v[i];
		if(r>n+2)break;
		for(int j=0;j<v.size()&&v[j]<r;j++){
			int p=v[j];
			int q=r-p;
			if(IsPrime(q)){
				ans++;
				// cout << p << "," << q << "," << r << endl;
			}
		}
	}

	cout << ans << endl;
    return 0;
}