%This macro provides the math text for the second column of page 5 % %The macro has one parameter: % 1) The width of the text \newcommand\TFiveGrapheOne[1]{% \def\LineOfArray##1##2{##1&{\raggedright ##2}\\} \parbox[t]{#1}{% %Space dedicated to the explanation of the graph's %vocabulary in the tabular environment \deflength{\HSpace}{.70#1} \TFiveGraphFontSize %Since the column is narrow, ragged at right %produces better spacing % \raggedright \TFiveTitle{Definitions:} \begin{tabular}{@{}l@{\hspace{.25em}}p{\HSpace}} \LineOfArray{Loop}{An edge connecting a vertex to itself.} \LineOfArray{Directed}{Each edge has a direction.} \LineOfArray{Simple}{Graph with no loops or multi-edges.} \LineOfArray{Walk}{A sequence $v_0e_1v_1\ldots e_\ell v_\ell$.} \LineOfArray{Trail}{A walk with distinct edges.} \LineOfArray{Path}{A trail with distinct vertices.} \LineOfArray{Connected}{A graph where there exists a path between any two vertices.} \LineOfArray{Component}{A maximal connected subgraph.} \LineOfArray{Tree}{A connected acyclic graph.} \LineOfArray{Free tree}{A tree with no root.} \LineOfArray{DAG}{Directed acyclic graph.} \LineOfArray{Eulerian}{Graph with a trail visiting each edge exactly once.} \LineOfArray{Hamiltonian}{Graph with a cycle visiting each vertex exactly once.} \LineOfArray{Cut}{A set of edges whose removal increases the number of components.} \LineOfArray{Cut-set}{A minimal cut.} \LineOfArray{Cut edge}{A size 1 cut.} \LineOfArray{k-Connected}{A graph connected with the removal of any $k-1$ vertices.} \LineOfArray{k-Tough}{$\forall S \subseteq V, S \neq \emptyset$ we have $k\cdot c(G-S) \leq \vert S \vert$.} \LineOfArray{k-Regular}{A graph where all vertices have degree $k$.} \LineOfArray{k-Factor}{A $k$-regular spanning subgraph.} \LineOfArray{Matching}{A set of edges, no two of which are adjacent.} \LineOfArray{Clique}{A set of vertices, all of which are adjacent.} \LineOfArray{Ind. set}{A set of vertices, none of which are adjacent.} \LineOfArray{Vertex cover}{A set of vertices which cover all edges.} \LineOfArray{Planar graph}{A graph which can be embeded in the plane.} \LineOfArray{Plane graph}{An embedding of a planar graph.} \end{tabular} \TFiveTitle{Planar graphs} \AdjustSpace{1ex plus .5ex minus .2ex} \begin{DisplayFormulae}{1}{0pt}{4ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{\sum_{v\in V} \deg(v) = 2 m} \end{DisplayFormulae} \AdjustSpace{1ex plus .5ex minus .2ex} If $G$ is planar then $n - m + f = 2$, so \AdjustSpace{1ex plus .5ex minus .2ex} \begin{DisplayFormulae}{1}{0pt}{4ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{f \leq 2n - 4, \quad m \leq 3 n - 6} \end{DisplayFormulae} \AdjustSpace{1ex plus .5ex minus .2ex} Any planar graph has a vertex with degree $\leq 5$. \TFiveTitle{Notation:} \begin{tabular}{@{}lp{\HSpace}} \LineOfArray{$E(G)$}{Edge set} \LineOfArray{$V(G)$}{Vertex set} \LineOfArray{$c(G)$}{Number of components} \LineOfArray{$G[S]$}{Induced subgraph} \LineOfArray{$\deg(v)$}{Degree of $v$} \LineOfArray{$\Delta(G)$}{Maximum degree} \LineOfArray{$\delta(G)$}{Minimum degree} \LineOfArray{$\chi(G)$}{Chromatic number} \LineOfArray{$\chi_E(G)$}{Edge chromatic number} \LineOfArray{$G^c$}{Complement graph} \LineOfArray{$K_n$}{Complete graph} \LineOfArray{$K_{n_1,n_2}$}{Complete bipartite graph} \LineOfArray{$\ramsey(k,\ell)$}{Ramsey number} \end{tabular} } }