def divisor(num)
  result = []
  i = 1
  while (i*i) <= num do
    remainder = num % i
    if remainder == 0
      result << i
      if i*i!=num
          result<<(num/i)
      end
    end
    i += 1
  end
  return result
end
  
  
  
@n=gets.to_i
count=0

for i in 1..@n-1
    v=@n-i
    count+=divisor(v).length
end
p count
