bijection
mathematical function which is a one-to-one mapping of sets
k-permutation
selection of some objects in a particular order
permutation
change of ordering in a (mathematical) set
homeomorphism
isomorphism between topological spaces; continuous bijection with continuous inverse
collineation
bijection from one projective space to another that preserves collinearity
pairing function
function which encodes two natural numbers into a single natural number
active and passive transformation
distinction between meanings of Euclidean space transformations
identity function
function that always returns the same value that was used as its argument
involution
function that is its own inverse