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Mar
31
comment All non-isomorphic transitive actions of the Dihedral group
@DerekHolt Could you please elaborate a bit more about this? I spent a day on it but don't see an easy way to deduce that for $n$ odd we only need consider subgroups up to conjugacy and the structure of the isomorphism classes under $\rm{Aut}(G)$. Thanks
Mar
30
comment All non-isomorphic transitive actions of the Dihedral group
@LeeMosher Which theorem exactly? I only covered Lemma1.6B which allows one to find transitive actions up to equivalence.
Mar
30
comment All non-isomorphic transitive actions of the Dihedral group
@LeeMosher Yes, but I don't know how this gives me all actions of $D_n$ modulo isomorphism
Mar
30
asked All non-isomorphic transitive actions of the Dihedral group
Mar
27
accepted Outer automorphism of $S_6$ and conjugate stabilizers
Mar
25
comment Outer automorphism of $S_6$ and conjugate stabilizers
Could you please clarify why $g((1,2))$ commutes with every element of the stabilizer of $1$ and $2$? Why does it follow that $g$ is the identity map? Is it because it fixes all the transpositions?
Mar
25
asked Outer automorphism of $S_6$ and conjugate stabilizers
Mar
7
accepted Bounding probability of some events with bounded depdendence
Mar
6
comment Bounding probability of some events with bounded depdendence
@Math1000 The complement of the event $A_1.$
Mar
6
asked Bounding probability of some events with bounded depdendence
Feb
26
comment Probabilistic method: vertex disjoint cycles in digraphs
@ManuelLafond Interesting. Where did you find this proof? I think one can fix it by using the asymmetric LLL perhaps at the expense of a worse constant.
Feb
26
comment Probabilistic method: vertex disjoint cycles in digraphs
@ManuelLafond I've spoken with the author and he confirmed its a mistake. One would somehow have to include this event C as well.
Feb
25
asked Probabilistic method: vertex disjoint cycles in digraphs
Feb
19
comment Does there exists a $k$-critical graph having connectivity $2$ for every $k\geq 3$?
Note that by definition, $K_k$ is $2$-connected for any $k > 2.$
Feb
18
comment For every r exists large enough n such that any graph…
Which propositions are you allowed to use then?
Feb
17
comment Finding the spanning subgraphs of a complete bipartite graph
@chowching I suggest that for a start you look at Harary's and Palmer's book called "graphical enumeration"
Feb
17
comment Finding the spanning subgraphs of a complete bipartite graph
@chowching You can but the formula will most likely require using computer computations.
Feb
17
comment Finding the spanning subgraphs of a complete bipartite graph
@chowching You should be more specific about what you're looking for. Note that in general there is no closed formula for the number of bipartite graphs with bipartitions of cardinality n and m.
Feb
17
comment min degree at least $n+1/2$, every edge on Hamilton cycle
I guess you must visualize this thing. Just to be sure $G/e$ denotes the graph obtained by contracting the edge $e$?
Feb
17
comment min degree at least $n+1/2$, every edge on Hamilton cycle
That should be enough. If you extend the hamiltonian cycle in $G'$ to a cycle of $G$ it uses the edge $e$