Timeline for counting trees with two kind of vertices and fixed number of edges beetween one kind
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 19, 2012 at 11:48 | vote | accept | Patt Geffrey | ||
| Jun 14, 2012 at 5:48 | answer | added | Brendan McKay | timeline score: 5 | |
| Jun 13, 2012 at 16:48 | comment | added | Gerhard Paseman | Here is a suggested way to count the quantity. Take a tree T and select t edges from it. Compute the number of vertices k incident to these t edges. Paint the k vertices with a subset of the first j vertices, and then paint the rest of the vertices. You will end up for that tree T with a weighted sum of terms of the form k!(n-k)! as the number of ways to color that tree, with the sum ranging over t-subsets of edges of T. The nice thing is that k is bounded by simple functions of t, so you can roughly approximate the sum quickly. Gerhard "Ask Me About System Design" Paseman, 2012.06.13 | |
| Jun 13, 2012 at 15:50 | history | asked | Patt Geffrey | CC BY-SA 3.0 |