cardinality
measure of the “number of elements of the set”, either as a cardinal number or as the equivalence class of sets admitting bijections to this set
rank of a group
cardinality of a basis of the group
matching number
size of a maximum matching in a graph
edge cover number
size of a minimum edge cover in a graph without isolated vertices
order type
two ordered sets X,Y are said to have the same order type just when they are order isomorphic, that is, when there exists a bijection f: X → Y such that both f and its inverse are strictly increasing
uniqueness
philosophical category, opposite of multiplicity; state or condition wherein something is unlike anything else in comparison
vertex cover number
size of a vertex cover of minimum size
infinity
mathematical concept
independence number
size of an independent set of graph vertices of maximal size
group order
numbering of elements in a group
clique number
size of a graph clique of maximal size