Mathematics to be formalized next
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This document lists the material that I would like to see added to IsarMathLib in the near future. It is intended as a suggestion for contributors.

1. Sequences defined recursively
It is quite frequent in math that we define a sequence (that is, a function on naural numbers) by specifying the first element and a rule for creating new values from previous one(s). It would be nice to have an implementation of this in the ZF framework that does not use the word "datatype".

2. Algebraic topology
We have topology, we have groups, let's have topological groups.

3. Metric spaces
Let's start from defining a metric as a function with values in an ordered group with some desired properties, then see what is needed for different properties of metric spaces.

4. Real and complex analysis. 
The right way to do this is to start with a model of real numbers (a complete ordered field), then define complex numbers constructively and prove that the resulting structure satisfies the axioms of complex numbers, as specified in the Metamath database. Then import the knowledge from Metamath.

5. Examples
Real numbers allow to provide lots of examples of groups, rings, fields, topologies and metric spaces.

Modified 09/26/06