This is an example exercise from my Algebra class:
Find the antisymmetric closure of $$R=\{(1,2),(1,3),(2,2),(2,1)\}$$ on $$\{1,2,3\}$$
I don't see it explicitly defined in the lecture notes and I couldn't find much information about Antisymmetric Closure online.
I sort of understand Reflexive, Symmetric and Transitive Closure, but not Antisymmetric Closure. How is it defined and how can I find it?