Basics
the plan:
Logic
Set Theory: family/collection of sets, empty set, inclusion, power set, union and intersection, disjoint, limit superior/inferior, difference, symmetric difference, complement, deMorgan´s laws, Cartesian product
Orderings
Mappings: map, composition, image, inverse image, domain, range, injective, surjective, bijective, inverse map
Cardinality Schröder-Bernstein Theorem
Sequences