title: Problems with lists and multiplication table
body: <p>I need to build a function that takes two positive integers and returns a list of lists representing a multiplication table for multiplying all integers from 0 up to the given number. So for example, <code>times_table(3,5)</code> should return </p>
  
  <pre><code>[[0, 0, 0, 0,  0,  0], 
   [0, 1, 2, 3,  4,  5], 
   [0, 2, 4, 6,  8, 10], 
   [0, 3, 6, 9, 12, 15]]  
  </code></pre>
  
  <p>However, the function can only do this : <code>4 = 4 , 8 , 12 , 16</code>.  Also, I cant figure out how to make it in (x,y) format.</p>
  
  <hr>
  
  <p>This is what I have so far:</p>
  
  <pre><code>def times_table(s):
      n=int(input('Please enter a positive integer between 1 and 15: '))
      for row in range(1,n+1):
          s = ''
      for col in range(1,n+1):
          s += '{:3} '.format(row * col)
      print(s)
  </code></pre>
  
  <p>Help if you can...</p>