I recently started using mysql, and I'm trying out some stuff to learn a bit more. I decided to implement a small music charts system: it will hold the data telling you which song is on which position in a certain week. For now, I use two tables:

[outlaw41]
week
position1
position2
position3
(..all the way to...)
position40
position41

[song]
index
title
artist
album

The second table (song) holds information on the songs themselves. Index is a unique integer.
The first table (outlaw41) holds the information on the charts. Each week, a new row is added, reflecting the charts of that week (which song was on number one, which one was number 2, etc).

My question is: how do I link these tables? Somehow, I want to tell the [outlaw41] table that week3's position1 is the song with index x in the [song] table.