Transitive action on two sets!
99346
Prove a result on transitive group actions.
97800
Exterior power "commutes" with direct sum
37331
Prove that every set with more than one element has a permutation without fixed points
118595
Proving that a set is countable by finding a bijection
113391
Prove that if $A$ is transitive, then $\mathcal{P}(A)$ is transitive too.
158355
If $A$ commutes with $B$ and $B$ commutes with $C$, then $A$ commutes with $C$
137921
Reflexivity, Transitivity, Symmertry of the square of an relation
87830
Relating the union of the power set of a set to the set itself
57954
How many transitive relations on a set of $n$ elements?
1627
Cartesian product of an arbitrary number of sets
17935
Can a relation with less than 3 elements be considered transitive?
2935
Completness and Set of Result of One Set ?!?
140563
Concrete examples of group actions.
128060
Proof that the relation $5 \mid (a + 4b)$ is symmetric and transitive
72551
Proof that $\rho = \pm1$ implies linear combination
89506
Union of disjoint sets : Equivalence relations
110325
proof of basic fact that torus actions are diagonalizable