#include <iostream>
#include <queue>
#include <map>
#include <list>
#include <vector>
#include <string>
#include <stack>
#include <limits>
#include <climits>
#include <cassert>
#include <fstream>
#include <cstring>
#include <cmath>
#include <bitset>
#include <iomanip>
#include <algorithm>
#include <functional>
#include <cstdio>
#include <ciso646>
#include <set>
#include <array>
#include <unordered_map>

using namespace std;

#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)

#define inf 0x3f3f3f3f
#define PB push_back
#define MP make_pair
#define ALL(a) (a).begin(),(a).end()
#define SET(a,c) memset(a,c,sizeof a)
#define CLR(a) memset(a,0,sizeof a)
#define VS vector<string>
#define VI vector<ll>
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define MIN(a,b) (a>b?b:a)
#define MAX(a,b) (a>b?a:b)
#define pi 2*acos(0.0)
#define INFILE() freopen("in0.txt","r",stdin)
#define OUTFILE()freopen("out0.txt","w",stdout)
#define ll long long
#define ull unsigned long long
#define pii pair<ll,ll>
#define pcc pair<char,char>
#define pic pair<ll,char>
#define pci pair<char,ll>
#define eps 1e-14
#define FST first
#define SEC second
#define SETUP cin.tie(0), ios::sync_with_stdio(false), cout << setprecision(15)

namespace {
	struct input_returnner {
		ll N; input_returnner(ll N_ = 0) :N(N_) {}
		template<typename T> operator vector<T>() const { vector<T> res(N); for (auto &a : res) cin >> a; return std::move(res); }
		template<typename T> operator T() const { T res; cin >> res; return res; }
		template<typename T> T operator - (T right) { return T(input_returnner()) - right; }
		template<typename T> T operator + (T right) { return T(input_returnner()) + right; }
		template<typename T> T operator * (T right) { return T(input_returnner()) * right; }
		template<typename T> T operator / (T right) { return T(input_returnner()) / right; }
		template<typename T> T operator << (T right) { return T(input_returnner()) << right; }
		template<typename T> T operator >> (T right) { return T(input_returnner()) >> right; }
	};
	template<typename T> input_returnner in() { return in<T>(); }
	input_returnner in() { return input_returnner(); }
	input_returnner in(ll N) { return std::move(input_returnner(N)); }
}

const ll MOD = 1e9 + 7;

struct ModInt {
	ll v = 0;
	ModInt() {}
	template<class T> ModInt(const T& right) {
		v = right;
		if (v >= 0) v %= MOD;
		else v += ((-v) / MOD + 1)*MOD;
		v %= MOD;
	}
	void operator = (const ModInt& right) { v = right.v; }
	template<class T> void operator = (const T& right) {
		v = right;
		if (v >= 0) v %= MOD;
		else v = v += ((-v) / MOD + 1)*MOD;
		v %= MOD;
	}

	ModInt operator + (const ModInt& right) { return (v + right.v) % MOD; }
	ModInt operator - (const ModInt& right) { return (MOD - (v - right.v)); }
	ModInt operator * (const ModInt& right) { return (v * right.v) % MOD; }
	ModInt operator / (const ModInt& right) { return v / right.v; }

	void operator += (const ModInt& right) { v = (v + right.v) % MOD; }
	void operator -= (const ModInt& right) { v = (MOD - (v - right.v)); }
	void operator *= (const ModInt& right) { v = (v* right.v) % MOD; }
	void operator /= (const ModInt& right) { v = v / right.v; }

	bool operator == (const ModInt& right) { return v == right.v; }
};

ostream& operator << (ostream& os, const ModInt& value) {
	os << value.v;
	return os;
}

string YN[] = { "No", "Yes" };

void solve();
/// ---template---

#define int ll

int gcd(int a, int b) {
	return b != 0 ? gcd(b, a % b) : a;
}

signed main() {
	SETUP;
	solve();
#ifdef _DEBUG
	system("pause");
#endif
	return 0;
}

class prime {
private:
public:
	std::vector<int> primes;
	std::vector<bool> isPrime;
	prime(int num = 0) {
		if (num == 0) return;
		isPrime.resize(num + 1);
		fill(isPrime.begin(), isPrime.end(), true);
		int ma = sqrt(num) + 1;
		isPrime[0] = isPrime[1] = false;
		int cnt = 0;
		for (int i = 2; i <= ma; ++i) if (isPrime[i]) {
			for (int j = 2; i*j <= num; ++j) {
				isPrime[i*j] = false;
				cnt++;
			}
		}
		primes.reserve(cnt);
		for (int i = 0; i<isPrime.size(); ++i) if (isPrime[i]) {
			primes.push_back(i);
		}
	}

	bool IsPrime(int num) {
		if (num < isPrime.size()) return isPrime[num];
		for (auto p : primes) {
			if (num%p == 0) return false;
		}
		int ma = sqrt(num) + 1;
		for (int i = primes.back(); i <= ma; i += 2) {
			if (num%i == 0) return false;
		}
		return true;
	}

	std::map<int, int> GetFactor(int num) {
		std::map<int, int> res;
		int ma = sqrt(num) + 1;
		int a = 2;
		auto it = primes.begin();
		while (num >= a*a) {
			if (num%a == 0) {
				res[a]++;
				num /= a;
			}
			else {
				if (it == primes.end()) ++a;
				else {
					++it;
					a = *it;
				}
			}
		}
		res[num]++;
		return res;
	}
};

void solve() {
	prime p(100002);
	int Q; cin >> Q;
	vector<int> cnt(100002);
	cnt[0] = 0;
	REP(i, cnt.size() - 1) {
		if (i % 2 == 0) {
			cnt[i + 1] = cnt[i];
		}
		else {
			cnt[i + 1] = cnt[i] + (p.IsPrime(i) and p.IsPrime((i + 1) / 2));
		}
	}
	REP(i, Q) {
		int l, r; cin >> l >> r;
		cout << cnt[r+1] - cnt[l] << endl;
	}
}


Measured memory_bytes: 1536