Barvanja ravninskih in sorodnih družin grafov : doktorska disertacija
Erman, Rok
Predstavimo štiri rezultate v naslednjem vrstnem redu: seznamsko barvanje kvadrata ravninskih grafov, realno označevanje poddružine Kneserjevih grafov, linearno barvanje ravninskih grafov in navadno ...barvanje skoraj ravninskih grafov. Najprej podamo zgornje meje za izbirno število kvadrata ravninskega grafa z maksimalno stopnjo ▫$\Delta \le 4$▫. V posebnem je ▫$G^2$▫ 5-, 6-, 7-, 8-,9-, 12-, 14- ali 15-izbiren, če je ožina grafa ▫$G$▫ vsaj 20, 15, 10, 8, 7, 5, 4 ali 3. Določimo lambda funkcijo ▫$\lambda$▫ za poddružino Kneserjevih grafov. ▫$$\lambda(K(1\ell + 1,2);x, 1) = \begin{cases} 2\ell + (\ell - 1)x & \text{za } x \in \langle 0, 1/\ell),\\ (2\ell^2 + \ell - 1)x & \text{za } x \in \langle 1/\ell, 1),\\ 2\ell^2 + \ell - 1 & \text{za } x \in \langle 1, 3),\\ (2\ell - 2)x + 2\ell^2 - 5\ell + 5 & \text{za } x \ge 3, \end{cases}$$▫ in ▫$$\lambda(K(1\ell + 2,2);x, 1) = \begin{cases} 2\ell + 3\ell x & \text{za } x \in \langle 0, 1/\ell),\\ (2\ell^2 + 3\ell)x & \text{za } x \in \langle 1/\ell, 1),\\ 2\ell^2 + 3\ell & \text{za } x \in \langle 1, 3),\\ (2\ell - 1)x+ 2\ell^2 - 3\ell + 3 & \text{za } x \ge 3. \end{cases}$$▫ Dokažemo, da za linearno kromatično število ▫$\text{lc}(G)$▫ ravninskega grafa ▫$G$▫ z ožino ▫$g \ge 8$▫ in maksimalno stopnjo ▫$\Delta \ge 7$▫ velja neenakost ▫$\text{lc}(G) \le \lceil \frac{\Delta}{2} \rceil +1$▫. Pokažemo tudi, da za vsak graf s prekrižnim številom največ 4 in kličnim številom največ 5 obstaja 5-barvanje. Prav tako dokažemo, da je graf s kličnim številom največ 5, ki mu lahko odstranimo 3 povezave in s tem postane ravninski, nujno 5-obarvljiv.
Type of material - dissertation
; adult, serious
Publication and manufacture - Ljubljana : [R. Erman], 2012
It was not necessary to add the material to the shelf.
Bibliographic material was successfully added on shelf.
Adding bibliographical material on shelf was not successful.
Material is already on the shelf.
Permalink
URL:
Impact factor
Access to the JCR database is permitted only to users from Slovenia. Your current IP address is not on the list of IP addresses with access permission, and authentication with the relevant AAI accout is required.
Year
Impact factor
Edition
Category
Classification
JCR
SNIP
JCR
SNIP
JCR
SNIP
JCR
SNIP
Select the library membership card:
DRS,
in which the journal is indexed
Database name
Field
Year
Links to authors' personal bibliographies
Links to information on researchers in the SICRIS system
Subject headings in COBISS General List of Subject Headings
Select pickup location
The material from the parent unit is free. If the material is delivered to the pickup location from another unit, the library may charge you for this service.
