Algebraic aspects of Lê numbers

The Milnor number is the most important algebraic/topological invariant associated to an isolated singular point of a complex hypersurface. The Lê numbers are a generalization of the Milnor number to non-isolated hypersurface singularities.

I will give the algebraic definition of the Lê numbers, calculate them in a non-trivial example, and then give and sketch proofs of some algebraic results involving these numbers. I will end by characterizing the Lê numbers via a formal algebraic process into which one inputs only the constructible function given by the reduced Euler characteristics of the Milnor fibers.