If by "combining numbers into music" you mean obtaining symbolic representation of music (i.e. score that you will give to musicians, MIDI, etc.), Python might be a low-hanging fruit. There are many modules for all kinds of scientific computing and visualization, Music21 is made for handling musical structures on any level and can export to MIDI, MusicXML, Lilypond, and probably other formats. The language is "easy" to learn and there are tons of resources for learning and growing. You could probably even do the maths in a spreadsheet of your choice and use Python + Music21 only to convert your CSV file to a score.

For explorations on the level of sound synthesis or DSP, you'll probably want to look into SuperCollider, FAUST or CSound, the choice will be hard to make. Nyquist (Lisp syntax) is part of Audacity, so that might be one possible path.

So is PowerPoint :P

Cheers,

Michał