%0 Journal Article %T Partitioning of Any Infinite Set with the Aid of Non-Surjective Injective Maps and the Study of a Remarkable Semigroup %A Charif Harrafa %J Open Journal of Discrete Mathematics %P 74-88 %@ 2161-7643 %D 2020 %I Scientific Research Publishing %R 10.4236/ojdm.2020.103008 %X In this article, we will present a particularly remarkable partitioning method of any infinite set with the aid of non-surjective injective maps. The non-surjective injective maps from an infinite set to itself constitute a semigroup for the law of composition bundled with certain properties allowing us to prove the existence of remarkable elements. Not to mention a compatible equivalence relation that allows transferring the said law to the quotient set, which can be provided with a lattice structure. Finally, we will present the concept of Co-injectivity and some of its properties. %K Partitioning %K Non-Surjective %K Injective %K Infinite Set %K Fixed Points %K Lattice Structure %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=101368