Example of a relation that is symmetric and transitive, but not reflexive
31392
Examples and Counterexamples of Relations which Satisfy Certain Properties
75985
Given the functional dependencies of a relation is there more then one way to normalize it?
25553
elementary set theory (cartesian product and symmetric difference proof)
34798
Example of element of double dual that is not an evaluation map
98027
Non-finite clause complementation of complex transitive verbs
108309
An example of a non-abelian group of order $p^3$
18462
Transitivity check vs. Transitive Closure
9066
Whats the difference between Antisymmetric and reflexive? (Set Theory/Discrete math)
85819
A non-polyhedral pair $(X,A)$ with both $X$ and $A$ polyhedral
74114
How to find the number of anti-symmetric relations?
1643
Number of reflexive relations defined on a set A with n elements
130620
Identity type between A and B being non-empty implies non-emptiness of A and B?
56512
Divisibility is transitive: $\ a\mid b\mid c\,\Rightarrow\ a\mid c$
32127
Example where $f\circ g$ is bijective, but neither $f$ nor $g$ is bijective
64261
example of not surjective isometry on a bounded not closed set.
142887
Exercise 1 pg 33 from "Algebra - T. W. Hungerford" - example for a semigroup-hom but not monoid-hom..
115350
An example of a Banach space isomorphic but not isometric to a dual Banach space