Timeline for Minimal hypergraphs with respect to separation
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
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| Nov 20, 2014 at 23:05 | comment | added | bof | @AlexDegtyarev, I see. I don't think that by "minimal" the OP means a $T_1$ structure $E$ which is a subset of every $T_1$ structure; I think he means a $T_1$ structure $E$ such that no proper subset of $E$ is a $T_1$ structure. This is the usual meaning of "minimal element" in English; the other would be called "minimum" or "least element". | |
| Nov 20, 2014 at 20:22 | comment | added | Alex Degtyarev | I claim that on the four element set there are two hypergraph structures (the complete "honest" graph $K_4$ and the graph whose edges are all one-element sets) which are both $T_1$ but, on the other hand, their intersection is empty (which is obviously not $T_1$). Hence, there's no minimal $T_1$ structure. | |
| Nov 20, 2014 at 12:57 | comment | added | Alex Degtyarev | This is huge! Just $K_4$ and the "graph" on the same four vertices and edges all one-element sets would do. The "intersection" of these "graph" structures has empty edge set, hence obviously not $T_1$. | |
| Nov 20, 2014 at 11:12 | vote | accept | Dominic van der Zypen | ||
| Nov 20, 2014 at 10:58 | history | edited | bof | CC BY-SA 3.0 |
added 7 characters in body
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| Nov 20, 2014 at 10:53 | history | answered | bof | CC BY-SA 3.0 |