diff options
| author | Juan Marín Noguera <juan.marinn@um.es> | 2021-01-12 22:03:47 +0100 |
|---|---|---|
| committer | Juan Marín Noguera <juan.marinn@um.es> | 2021-01-12 22:03:47 +0100 |
| commit | 50bd6d001decbdd14914b23223644c08709fc816 (patch) | |
| tree | 7113f7686f1f787fcc6a9e88d284dffb9729ad8e /graf | |
| parent | c2d7895721d5100280efb6c3644ec22598dce84e (diff) | |
Inicio tema 5
Diffstat (limited to 'graf')
| -rw-r--r-- | graf/n.lyx | 14 | ||||
| -rw-r--r-- | graf/n5.lyx | 327 |
2 files changed, 341 insertions, 0 deletions
@@ -257,5 +257,19 @@ filename "n4.lyx" \end_layout +\begin_layout Chapter +Coloración de grafos +\end_layout + +\begin_layout Standard +\begin_inset CommandInset include +LatexCommand input +filename "n5.lyx" + +\end_inset + + +\end_layout + \end_body \end_document diff --git a/graf/n5.lyx b/graf/n5.lyx new file mode 100644 index 0000000..d4c4f1b --- /dev/null +++ b/graf/n5.lyx @@ -0,0 +1,327 @@ +#LyX 2.3 created this file. For more info see http://www.lyx.org/ +\lyxformat 544 +\begin_document +\begin_header +\save_transient_properties true +\origin unavailable +\textclass book +\use_default_options true +\begin_modules +algorithm2e +\end_modules +\maintain_unincluded_children false +\language spanish +\language_package default +\inputencoding auto +\fontencoding global +\font_roman "default" "default" +\font_sans "default" "default" +\font_typewriter "default" "default" +\font_math "auto" "auto" +\font_default_family default +\use_non_tex_fonts false +\font_sc false +\font_osf false +\font_sf_scale 100 100 +\font_tt_scale 100 100 +\use_microtype false +\use_dash_ligatures true +\graphics default +\default_output_format default +\output_sync 0 +\bibtex_command default +\index_command default +\paperfontsize default +\spacing single +\use_hyperref false +\papersize default +\use_geometry false +\use_package amsmath 1 +\use_package amssymb 1 +\use_package cancel 1 +\use_package esint 1 +\use_package mathdots 1 +\use_package mathtools 1 +\use_package mhchem 1 +\use_package stackrel 1 +\use_package stmaryrd 1 +\use_package undertilde 1 +\cite_engine basic +\cite_engine_type default +\biblio_style plain +\use_bibtopic false +\use_indices false +\paperorientation portrait +\suppress_date false +\justification true +\use_refstyle 1 +\use_minted 0 +\index Index +\shortcut idx +\color #008000 +\end_index +\secnumdepth 3 +\tocdepth 3 +\paragraph_separation indent +\paragraph_indentation default +\is_math_indent 0 +\math_numbering_side default +\quotes_style french +\dynamic_quotes 0 +\papercolumns 1 +\papersides 1 +\paperpagestyle default +\tracking_changes false +\output_changes false +\html_math_output 0 +\html_css_as_file 0 +\html_be_strict false +\end_header + +\begin_body + +\begin_layout Standard +Dado un grafo +\begin_inset Formula $G=(V,E)$ +\end_inset + + y un conjunto +\begin_inset Formula $S$ +\end_inset + + de +\series bold +colores +\series default +, llamamos +\series bold +coloración +\series default + ( +\series bold +propia por vértices +\series default +) de +\begin_inset Formula $G$ +\end_inset + + a una función +\begin_inset Formula $f:V\to S$ +\end_inset + + con +\begin_inset Formula $f(u)\neq f(v)$ +\end_inset + + para +\begin_inset Formula $(u,v)\in E$ +\end_inset + +. + Si +\begin_inset Formula $|S|=k$ +\end_inset + +, +\begin_inset Formula $f$ +\end_inset + + es una +\series bold + +\begin_inset Formula $k$ +\end_inset + +-coloración +\series default +, y +\begin_inset Formula $G$ +\end_inset + + es +\series bold + +\begin_inset Formula $k$ +\end_inset + +-coloreable +\series default + si admite una +\begin_inset Formula $k$ +\end_inset + +-coloración. + Una +\begin_inset Formula $k$ +\end_inset + +-coloración +\begin_inset Formula $f$ +\end_inset + + induce una partición de +\begin_inset Formula $V$ +\end_inset + + en subconjuntos independientes, dados por +\begin_inset Formula $f^{-1}(c)$ +\end_inset + + para +\begin_inset Formula $c\in S$ +\end_inset + +. +\end_layout + +\begin_layout Standard +El +\series bold +número cromático +\series default + de un grafo +\begin_inset Formula $G$ +\end_inset + +, +\begin_inset Formula $\chi(G)$ +\end_inset + +, es el menor +\begin_inset Formula $k$ +\end_inset + + tal que +\begin_inset Formula $G$ +\end_inset + + es +\begin_inset Formula $k$ +\end_inset + +-coloreable. + Ejemplos: +\end_layout + +\begin_layout Enumerate +\begin_inset Formula $\chi(K_{n})=n$ +\end_inset + +. +\end_layout + +\begin_deeper +\begin_layout Standard +En adelante el grafo a considerar será +\begin_inset Formula $(V,E)$ +\end_inset + + y +\begin_inset Formula $f$ +\end_inset + + será una coloración. + Entonces, en este caso, +\begin_inset Formula $f(i)\neq f(j)$ +\end_inset + + para +\begin_inset Formula $i\neq j$ +\end_inset + +, luego +\begin_inset Formula $f$ +\end_inset + + es inyectiva y su imagen tiene cardinal +\begin_inset Formula $|V|=n$ +\end_inset + +. +\end_layout + +\end_deeper +\begin_layout Enumerate +\begin_inset Formula $\chi(G)=1$ +\end_inset + + si y sólo si +\begin_inset Formula $G$ +\end_inset + + es no vacío y sin ejes. +\end_layout + +\begin_deeper +\begin_layout Enumerate +\begin_inset Argument item:1 +status open + +\begin_layout Plain Layout +\begin_inset Formula $\implies]$ +\end_inset + + +\end_layout + +\end_inset + +Si existiera +\begin_inset Formula $(u,v)\in E$ +\end_inset + + sería +\begin_inset Formula $f(u)\neq f(v)$ +\end_inset + + y por tanto +\begin_inset Formula $|f(V)|\geq2\#$ +\end_inset + +, y si fuera +\begin_inset Formula $V=\emptyset$ +\end_inset + + sería +\begin_inset Formula $|f(V)|=0\#$ +\end_inset + +. +\end_layout + +\begin_layout Enumerate +\begin_inset Argument item:1 +status open + +\begin_layout Plain Layout +\begin_inset Formula $\impliedby]$ +\end_inset + + +\end_layout + +\end_inset + +Claramente +\begin_inset Formula $|f(V)|\geq1$ +\end_inset + +, pero podemos tomar todos los nodos del mismo color. +\end_layout + +\end_deeper +\begin_layout Enumerate +\begin_inset Note Note +status open + +\begin_layout Plain Layout + +\end_layout + +\end_inset + + +\end_layout + +\end_body +\end_document |
