Hey Guitardocphil, Zurf and Stonebridge!
Interesting one! 
I was thinking Pythagoras meself while I was reading the first post, Stonebridge and indeed, you are right that Pythagoras was the first to link Maths and Music (recorded, at any rate.) He was the one who found that if you had a weight hanging from a string, if you halved the distance of tension, you ended up with the same note an octave higher (12th fret to open string) and if you doubled the weight but kept the length the same, you have the same increase in octave (increasing tension = tuning an octave higher than concert pitch, but I will not be held accountable for broken strings if you wish to try THIS!).
So, yeah as far as root maths contained in music - Pythagorus!
But Lieven did mention Fibonacci who, for anyone who aren't knowledge like I can (SDH*,) came up with the sequence whereby you start with 1 and add it to the number before it (in the first case 0) and carry on adding the last two numbers - 1, 1, 2, 3, 5, 7 etc.
Now if you look at that a musical element is straightaways visible - 1, 3 and 5 are root third and fifth that make up all major chords!
Take any major key and play the sequence (1 for root, etc) and play 1, 1, 2, 3, 5 - musical or not? If you like it, does it work with minors/others too? If you don't like it, does it work with minor/other keys better?
As for which came first, Maths or Music, I can't help thinking that early man would have had to have communicated "Two mamoths over there!" before they'd have sung/danced their Victory Kill song/danced and their Haven't We Got Full Bellies song/lethargic dance after that!
Interesting!
* Self Depracating Humour 
<-----<< On an even field, only talent prevails! >>----->
Gans Gwarak da yn dorn yu lel, gwyr lowen an golon!
>>-----> [color=#FF0000]Rudhes[/color] hag [color=yellow]Owres[/color], Kajima <-----<<
You need to increase the tension by 4 times to get the octave.