# Original solution
# -*- coding: utf-8 -*-
"""
https://beta.atcoder.jp/contests/abc084/tasks/abc084_d
TLE
"""
import sys
from sys import stdin
from math import ceil, floor
input = stdin.readline


def create_prime_list(limit):
    """ エラトステネスの篩でlimitまでの素数リストを求める
    https://ja.wikipedia.org/wiki/%E3%82%A8%E3%83%A9%E3%83%88%E3%82%B9%E3%83%86%E3%83%8D%E3%82%B9%E3%81%AE%E7%AF%A9
    """
    x = limit**0.5
    primes = []
    #print('x={0}'.format(x))
    nums = [x for x in range(2, limit+1)]
    while nums[0]<=x:
        primes.append(nums[0])
        current_prime = nums[0]
        nums = [x for x in nums if x%current_prime != 0]
    primes.extend(nums)
    return primes


def solve(queries):
    primes = set(create_prime_list(10**5))

    # 10000ごとのブロックに分けて答えを計算しておく
    p_numbers = []
    block_size = 10000
    for i in range(0, 10**5, block_size):
        ans = 0
        for j in range(i, i + block_size):
            if j in primes and ((j+1)//2) in primes:
                ans += 1
        p_numbers.append(ans)


    for l, r in queries:
        t1 = ceil(l / block_size) * block_size
        t2 = floor(r / block_size) * block_size

        if t1 >= t2:
            ans = 0
            for i in range(l, r+1, 2):
                if i in primes and ((i+1)//2) in primes:
                    ans += 1
            print(ans)
        else:
            ans = 0
            for i in range(l, t1, 2):
                if i in primes and ((i+1)//2) in primes:
                    ans += 1
            for i in range(t2+1, r, 2):
                if i in primes and ((i+1)//2) in primes:
                    ans += 1
            for i in range(t1//block_size, t2//block_size):
                ans += p_numbers[i]
            print(ans)


def main(args):
    queries = []
    Q = int(eval(input()))
    # Q = 0
    # queries.append((12351, 89999))
    for _ in range(Q):
        l, r = list(map(int, input().split()))
        queries.append((l, r))
    solve(queries)


if __name__ == '__main__':
    main(sys.argv[1:])


# Optimized solution
# -*- coding: utf-8 -*-
"""
https://beta.atcoder.jp/contests/abc084/tasks/abc084_d

"""
import sys
from sys import stdin
from math import ceil, floor
input = stdin.readline


def create_prime_list(limit):
    """ エラトステネスの篩でlimitまでの素数リストを求める
    https://ja.wikipedia.org/wiki/%E3%82%A8%E3%83%A9%E3%83%88%E3%82%B9%E3%83%86%E3%83%8D%E3%82%B9%E3%81%AE%E7%AF%A9
    """
    x = limit**0.5
    primes = []
    #print('x={0}'.format(x))
    nums = [x for x in range(2, limit+1)]
    while nums[0]<=x:
        primes.append(nums[0])
        current_prime = nums[0]
        nums = [x for x in nums if x%current_prime != 0]
    primes.extend(nums)
    return primes



def solve(queries):
    primes = set(create_prime_list(10**5))
    dp = [0] * (100000 + 1)

    p_num = 0
    for i in range(1, 100000, 2):
        if i in primes and ((i+1)//2) in primes:
            p_num += 1
        dp[i] = p_num

    for l, r in queries:
        if l == 1:
            ans = dp[r]
        else:
            ans = dp[r] - dp[l-2]
        print(ans)



def main(args):
    queries = []
    Q = int(eval(input()))
    # Q = 0
    # for _ in range(100000):
    #     queries.append((1, 99999))
    for _ in range(Q):
        l, r = list(map(int, input().split()))
        queries.append((l, r))

    solve(queries)


if __name__ == '__main__':
    main(sys.argv[1:])