// Original C++ solution (slower):
#include <iostream>

#include <bits/stdc++.h>

using namespace std;

const int N = 1e5 + 4;

int prime[N];

int cond[N];

int cumu[N];

void Fill()

{

    memset(prime,1,sizeof(prime));

    prime[0] = prime[1] = 0;

    for(int i = 2; i <= N; i++)

    {

        if(prime[i])

        {

            for(int j = i+i; j <= N; j+=i)

            {

                prime[j] = 0;

            }

        }

    }

}

void build()

{

    for(int i = 0; i < N; i++)

    {

        if((i % 2 != 0) && (prime[i]) && (prime[(i + 1) / 2]))

        {

            cond[i] = 1;

        }else

        {

            cond[i] = 0;

        }

    }



    for(int i = 0; i < N; i++)

    {

        if(i == 0)

        {

            cumu[i] = cond[i];

        }else

        {

            cumu[i] = cumu[i - 1] + cond[i];

        }

    }



}

int main()

{

    Fill();

    build();

    int q , l , r;

    cin >> q;





    for(int i = 0; i < q; i++)

    {

        cin >> l >> r;

        cout << cumu[r] - cumu[l - 1] << endl;

    }

    return 0;

}


// Optimized solution to the same problem (faster):
/// *********** Coded by Olium_MdioxideN ***********



#include <bits/stdc++.h>

using namespace std;

#define ll long long

#define llu unsigned long long

#define eb emplace_back

#define pb push_back

#define mp make_pair

#define ext exit(0)

#define fast ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0)

#define in_file freopen("input.txt", "r", stdin)

#define out_file freopen("output.txt", "w", stdout)

#define newl printf("\n")

#define nl '\n'

#define endl '\n'

#define sci(x) scanf("%d",&(x))

#define scll(x) scanf("%lld",&(x))

#define sci2(x,y) scanf("%d %d",&(x),&(y))

#define pr printf

#define forr(i,b,e) for(int (i)=(b); (i) <= (e); (i)++)

#define fors(i,x) for(auto (i)=(x).begin(); (i) != (x).end(); (i)++)

#define F first

#define S second

#define mset0(x) memset((x), 0, sizeof((x)));

#define mset1(x) memset((x), -1, sizeof((x)));

#define bs binary_search

#define all(x) (x).begin(),(x).end()

#define pqmin(x) priority_queue<x, vector<x>, greater<x> >

#define pqmax(x) priority_queue<x>

#define sortd(x) sort(all(x)); reverse(all(x));

#define vi vector<int>

#define pii pair<int,int>

#define mpii map<int,int>

#define elif else if

#define debug(x) cerr << "Debug: " << x << '\n';

#define pi 3.14159265358979323846D

#define gcd(x,y) __gcd(x,y)

#define lcm(x,y) __lcm(x,y)

#define runtime() cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n"

#define Int inputInt()        //new int input

#define Long inputLong()      //new long input

#define Double inputDouble()  //new double input

#define String inputString()  //new string input

inline int inputInt() { int tmp; scanf(" %d", &tmp); return tmp; }

inline ll inputLong() { ll tmp; scanf(" %lld", &tmp); return tmp; }

inline double inputDouble() { double tmp; scanf(" %lf", &tmp); return tmp; }

inline string inputString() { char tmpStr[1000010]; scanf(" %s", tmpStr); return tmpStr; }



template <typename type> inline type __lcm(type n1,type n2){ return n1*(n2/gcd(n1,n2)); }



class stdout_cus

{

    short float_prec = 7;

public:

    inline stdout_cus operator<<(const int& arg){ printf("%d",arg); return *this; }

    inline stdout_cus operator<<(const short& arg){ printf("%d",arg); return *this; }

    inline stdout_cus operator<<(const bool& arg){ printf("%d",arg); return *this; }

    inline stdout_cus operator<<(const unsigned int& arg){ printf("%u",arg); return *this; }

    inline stdout_cus operator<<(const unsigned short& arg){ printf("%u",arg); return *this; }

    inline stdout_cus operator<<(const long long& arg){ printf("%lld",arg); return *this; }

    inline stdout_cus operator<<(const unsigned long long& arg){ printf("%llu",arg); return *this; }

    inline stdout_cus operator<<(const double& arg){ printf("%.*f",float_prec,arg); return *this; }

    inline stdout_cus operator<<(const float& arg){ printf("%.*f",float_prec,arg); return *this; }

    inline stdout_cus operator<<(const char& arg){ printf("%c",arg); return *this; }

    inline stdout_cus operator<<(const unsigned char& arg){ printf("%c",arg); return *this; }

    inline stdout_cus operator<<(const char* arg){ printf("%s",arg); return *this; }

    inline stdout_cus operator<<(const std::string& arg){ printf("%s",arg.c_str()); return *this; }

    inline stdout_cus operator<<(const stdout_cus&){ return *this; }

    inline void flush() { fflush(stdout); }

    inline stdout_cus precision(short prec) { float_prec = prec; return *this; }

}cout_cus;

class stdin_cus

{

public:

    inline stdin_cus operator>>(const int& arg){ scanf(" %d",&arg); return *this; }

    inline stdin_cus operator>>(const short& arg){ scanf(" %d",&arg); return *this; }

    inline stdin_cus operator>>(const bool& arg){ scanf(" %d",&arg); return *this; }

    inline stdin_cus operator>>(const unsigned int& arg){ scanf(" %u",&arg); return *this; }

    inline stdin_cus operator>>(const unsigned short& arg){ scanf(" %u",&arg); return *this; }

    inline stdin_cus operator>>(const long long& arg){ scanf(" %lld",&arg); return *this; }

    inline stdin_cus operator>>(const unsigned long long& arg){ scanf(" %llu",&arg); return *this; }

    inline stdin_cus operator>>(const double& arg){ scanf(" %lf",&arg); return *this; }

    inline stdin_cus operator>>(const float& arg){ scanf(" %f",&arg); return *this; }

    inline stdin_cus operator>>(const char& arg){ scanf(" %c",&arg); return *this; }

    inline stdin_cus operator>>(const unsigned char& arg){ scanf(" %c",&arg); return *this; }

    inline stdin_cus operator>>(const char* arg){ scanf(" %s",arg); return *this; }

    inline stdin_cus operator>>(std::string& arg){ char tmp[1000000]; scanf(" %s",tmp); arg = tmp; return *this; }

    inline void flush() { fflush(stdin); }

}cin_cus;

#define cout cout_cus

#define cin cin_cus

#define sp cout.precision



/// * * *    Main Code Starts Now    * * *



#define MOD 10000007

#define MAX 100010

void olium();

#define sieve(x) normal_sieve(x)

vector<int> primes;

bool *isPrime = NULL;

int pidx = 0, csum[100010];

void normal_sieve(int n)

{

    n+=5;

    isPrime = new bool[n];

    memset(isPrime, 1, n);

    int sq = sqrt(n);

    isPrime[0] = isPrime[1] = false;

    for(int i = 4; i < n; i+=2) isPrime[i] = false;

    for(int i = 3; i <= sq; i+=2) if(isPrime[i]) for(int j = i*i; j < n; j+=(i<<1)) isPrime[j] = false;

}

int main()

{

    sieve(100100);

    for(int i = 1; i <= 100010; i++)

    {

        if(isPrime[i] && isPrime[((i+1)>>1)]) csum[i]++;

        csum[i] += csum[i-1];

    }

    //#ifndef ONLINE_JUDGE

    //in_file;

    //out_file;

    //#endif

    int t = 1;

    cin >> t;

    forr(i,1,t)

    {

        //cout << "Case " << i << ": ";

        olium();

    }

    return 0;

}



void olium()

{

    int l,r;

    cin >> l >> r;

    cout << csum[r] - csum[l-1] << nl;

}


// Fastest known solution for this problem: