[arethuza]

Describing computation in mathematical terms is arguably the core of Computer Science as a subject - particularly the "Theory of Computation":

http://en.wikipedia.org/wiki/Theory_of_computation

If you are interested in "functions/mappings" then you can look at Lambda Calculus and work your way right up to modern functional programming languages:

http://en.wikipedia.org/wiki/Lambda_calculus

[ssdfsdf]

I'm reasonably well versed in these topics, I found them unsatisfying, they don't capture the essence for me. I don't really know what I'm looking for I just know I haven't seen it yet.