output_description: Print the answer.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: a = int(input())
  b = 0
  for i in range(a):
      for k in range(i):
          if i % k == 0:
              b = b + 1
  print(b)
  
problem_description: Statement
  
  Given is a positive integer N. How many tuples (A,B,C) of positive integers
  satisfy A \times B + C = N?
samples: [{"input": "3", "output": "3\n    \n\nThere are 3 tuples of integers that satisfy A \\times B + C = 3: (A, B, C) =\n(1, 1, 2), (1, 2, 1), (2, 1, 1).\n\n* * *"}, {"input": "100", "output": "473\n    \n\n* * *"}, {"input": "1000000", "output": "13969985"}]