bio | website | rwoodroofe.math.msstate.edu |
---|---|---|
location | Starkville, MS | |
age | ||
visits | member for | 2 years, 11 months |
seen | 5 hours ago | |
stats | profile views | 504 |
Assistant Professor of Mathematics at Mississippi State University.
Oct 5 |
answered | Flag complexes that are shellable but not vertex decomposable |
Sep 24 |
awarded | Autobiographer |
Aug 30 |
comment |
Generalization of a theorem of Øystein Ore in group theory
There's also Roland Schmidt's nice book "Subgroup lattices of groups", which goes into a bit more depth on most of these and many related topics. |
Aug 12 |
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The Wedge Sum of path connected topological spaces
Link to amazon webpage for Hilton and Wylie is here: amazon.com/Homology-Theory-Introduction-Algebraic-Topology/dp/… |
Jul 28 |
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quasiprimitive non-solvable groups
John, that link looks wustl.edu specific. Try ams.org/mathscinet-getitem?mr=2661653 instead. (And no mathscinet access is required for that link.) |
Jul 7 |
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Factor subset of finite group
@Geoff Robinson: Yes, sounds like a good place to look for a possible counterexample. |
May 31 |
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Characterising extendable automorphisms
See also this related question mathoverflow.net/questions/7782/… |
May 31 |
revised |
Characterising extendable automorphisms
commented on difficulty of problem; other minor edits |
May 31 |
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Characterising extendable automorphisms
The groupprops wiki has a couple of articles regarding this, e.g. groupprops.subwiki.org/wiki/Extensible_automorphisms_problem . While I found these to be rather incomplete, they give a start in finding some references. |
May 31 |
answered | Characterising extendable automorphisms |
May 17 |
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When is $S_n \times S_m$ a subgroup of $S_p$?
It's maybe worth pointing out that 6! / (5! \cdot 3!) is an integer (is 1), so you can't rule this out purely from the index of the subgroup. |
May 2 |
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Sylow 3-subgroups of symmetric group
See also en.wikipedia.org/wiki/Symmetric_group#Sylow_subgroups |
Apr 17 |
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$2$-group with two isomorphic normal subgroups of index $4$ with non-isomorphic quotients
This question has a somewhat similar flavor to mathoverflow.net/questions/153433/… |
Mar 30 |
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Which graphs generate a matroidal independence complex?
My favorite example is the cross polytope (i.e., generalized octahedron), which is the independence complex of the disjoint union of $K_2$'s. |
Mar 28 |
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What have simplicial complexes ever done for graph theory?
Matoušek's nice book "Using the Borsuk-Ulam theorem" should be mentioned here. It is a grad-student accessible, book-length treatment of the Lovász solution to the Kneser problem and more recent improvements (and all the background you need to understand them). |
Mar 14 |
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matroids axioms and independence system
@user47659: Yes, that's what I mean. It's easiest to prove if you focus on the (minimal) non-faces of $\Delta$ and the circuits of matroids, rather than the faces and independent sets. Here face == independent set, in different terminology. |
Mar 12 |
answered | matroids axioms and independence system |
Feb 10 |
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Classification of automorphism groups of groups of order $p^4$
Yes, StructureDescription is limited. But is there a better alternative for getting a human-readable description of groups, suitable for MathOverflow? (I guess one easy improvement would be to only ask for the structure of the outer automorphism group.) |
Feb 10 |
answered | Classification of automorphism groups of groups of order $p^4$ |
Feb 9 |
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Classification of automorphism groups of groups of order $p^4$
It's not a complete answer to your question, but if you want to get some intuition, GAP (and hence SAGE) has a library of all groups of order $p^4$ built in. See gap-system.org/Packages/sgl.html |