output_description: Print Q lines. The i-th line (1≤i≤Q) should contain the response to the i-th
  query.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      Q
      l_1 r_1
      :
      l_Q r_Q
attempt: q = int(input())
  a = [list(int(i) for i in input().split()) for i in range(q)]
  MAX = 10**5
  is_prime = [1]*MAX
  for i in range(2, MAX):
      if not is_prime[i]:
          continue
      for j in range(i*2, MAX, i):
          is_prime[j] = 0
  s = [0]*MAX
  for i in range(3,MAX):
      s[i] = s[i-1] + 1 if is_prime[i] and is_prime[(i+1)//2]
  for i in range(q):
      l,r = a[i]
      print(s[r]-s[l-1])
problem_description: Statement
  
  We say that a odd number N is _similar to 2017_ when both N and (N+1)/2 are
  prime.
  
  You are given Q queries.
  
  In the i-th query, given two odd numbers l_i and r_i, find the number of odd
  numbers x similar to 2017 such that l_i ≤ x ≤ r_i.
samples: [{"input": "1\n    3 7", "output": "2\n    \n\n  * 3 is similar to 2017, since both 3 and (3+1)/2=2 are prime.\n  * 5 is similar to 2017, since both 5 and (5+1)/2=3 are prime.\n  * 7 is not similar to 2017, since (7+1)/2=4 is not prime, although 7 is prime.\n\nThus, the response to the first query should be 2.\n\n* * *"}, {"input": "4\n    13 13\n    7 11\n    7 11\n    2017 2017", "output": "1\n    0\n    0\n    1\n    \n\nNote that 2017 is also similar to 2017.\n\n* * *"}, {"input": "6\n    1 53\n    13 91\n    37 55\n    19 51\n    73 91\n    13 49", "output": "4\n    4\n    1\n    1\n    1\n    2"}]