There is relation that is symmetric and transitive but not reflexive?
10858
Why isn't reflexivity redundant in the definition of equivalence relation?
86025
Nonabelian semidirect products of order $pq$?
65308
Axiom of Choice: Family of non-empty sets mutually disjoint or not?
97801
If $R_{1}$ and $R_{2}$ are relations on a set S with $R_{1};R_{2}=R_{2};R_{1}$. Then $R_{1}$ and $R_{2}$ are bijective maps
4292
"Relation" versus "relationship"
142219
Does the splitting lemma hold without the axiom of choice?
13523
Are normal subgroups transitive?
85819
A non-polyhedral pair $(X,A)$ with both $X$ and $A$ polyhedral
9074
Example of non-isomorphic structures which are elementarily equivalent
41044
Equivalence of $a \rightarrow b$ and $\lnot a \vee b$
52305
Is there a general relation between $a/b$ and $(a+c)/(b+c)$ where $a,b,c > 0 $?
59577
Simple examples of uncorrelated but not independent $X$ and $Y$
151251
A simple algebra that is not semisimple
90879
Why correlation is not "transitive"?
83744
is there a property of a category that is preserved by category isomorphism, but not equivalence?
14877
Why is this relation not transitive?
113391
Prove that if $A$ is transitive, then $\mathcal{P}(A)$ is transitive too.