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Cambridge University Press 978-0-521-80230-7 - Topics in Topological Graph Theory Edited by Lowell W. Beineke and Robin J. Wilson Index More information Index absolute Galois group, 222 blocks of a transversal design, 269 accumulation point, 304 blocks of a triple system, 269 action of a group, 24, 226 book embedding, 327 adjacent edges, 2 boundary walk, 20 adjacent vertices, 2 bounded automorphism, 294 affine plane, 253 bouquet, 5, 50 algorithms, 30, 73, 330 bow-tie operation, 72 almost-4-connected graph, 306 branch decomposition, 84 almost homocyclic group, 216 branch set, 191 almost planar graph, 144 branched covering, 26, 191 almost-transitive graph, 293 bridge, 9, 89 angle transformation, 169 Brooks’s theorem, 9 apex graph, 76, 331 Burnside’s lemma, 184 arc, 10, 200 arc-transitive graph, 2 atom, 297 cactus, 38 attach an ear, 58 cage, 252 attach serially, 58 Cartesian product, 6 automorphism, 2, 22 Cayley graph, 28, 225 automorphism group, 2 Cayley map, 29, 210, 227 automorphism of a map, 201, 305 C-disc embedding, 68 average crossing number, 143 cellular embedding, 14, 20 average genus, 56 chiral map, 206 choosable graph, 126 chromatic index, 9 balanced automorphism, 213 chromatic number of a graph, 9 balanced Cayley map, 211 chromatic number of a map, 22 balanced representation, 155 chromatic number of a surface, 16, 22 bar, 46 circle packing representation, 66 bar-amalgamation, 46 circuit, 3 barycentric representation, 158 circular embedding, 20 barycentric subdivision, 169 circular embedding conjecture, 20, 320 base graph, 27, 182 closed surface, 19 bead of a necklace, 38 closed walk, 3 biembeddable pair, 271 closed-end ladder, 48 biembedding, 271 cobblestone path, 5, 49 Bilinski diagram, 307 co-degree of a face, 304 bipartite graph, 3 colony, 326 bisection width, 138 colouring a graph, 9, 111 blockage, 77 combinatorial configuration, 174 blocking curves, 77 combinatorial current graph, 26 341 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80230-7 - Topics in Topological Graph Theory Edited by Lowell W. Beineke and Robin J. Wilson Index More information 342 Index complement, 2 Desarguian plane, 250 complete bipartite graph, 5 d-fibre, 292 complete circuit, 282 diagonal curve, 122 complete graph, 4 diameter, 3 complete k-partite graph, 5 digraph, 10 component, 3 dilation coefficient, 154 concentric Bilinski diagram, 207 dipole, 5, 51 configuration embedding, 256 directed edge, 10 congestion of an edge, 138 directed graph, 10 congruent embeddings, 53 direction, 19 connected component, 3 disc, 175 connected covering, 185 disc embedding, 68 connected graph, 3 disc representation, 329 connectivity, 9 disconnected graph, 3 connectivity of an infinite graph, 296 disjoint crossing paths, 68 contractible, 8 displayed sets, 85 contraction of an edge, 8 distance, 3, 118 convex representation, 165 distribution of inverses, 211 core-free permutation group, 202 dominated end, 291 co-tree, 36 double ray, 290 covering, 26, 182 drawing of a graph, 135, 314 covering digraph, 27 duad, 262 covering graph, 27, 182 dual edge, 21 covering isomorphism, 182 dual embedding, 21 covering projection, 26, 181 dual map, 201 covering transformation, 182 dual vertex, 21 covering transformation group, 182 dual-width of an embedding, 146 cover, 327 Coxeter graph, 207 E-adjacent embeddings, 59 Cremona–Richmond geometry, 262 ear decomposition, 35 critical graph, 114 Earth–Moon colouring, 326 crosscap, 12 edge, 1 crosscap distribution polynomial, 47 edge fibre, 28 crosscap number, 16, 20, 47 edge-accumulation point, 303 crosscap range, 20, 47 edge-connectivity, 9 crossing number, 11, 23, 133, 136, 314 edge-homogeneous map, 308 crossing-critical graph, 139 edge-set, 1 crossing-free curves, 77 edge-symbol, 308 cubic graph, 2 edge-transitive graph, 2 current graph, 26, 281 edge-width, 324 cut-edge, 9 eigenpolytope, 177 cut-vertex, 8 eigenvector method, 156 cycle, 3 element of a geometry, 174 cycle double cover conjecture, 20, 320 elementary Abelian p-group, 216 cycle graph, 4 embeddable, 14 cycle rank, 34 embedding, 10, 14, 20, 153 cycle type, 309 embedding extension problem, 74 embedding a grid, 107 embedding in the plane, 10 dart group, 24, 200 embedding of a triple system, 270 decomposition of a graph, 84 embedding theory, 22 deficiency of a graph, 36 end vertex, 2 degree of a vertex, 2, 19 endpoint of a curve, 175 deletion of a vertex, 7 endpoint of an edge, 19 deletion of an edge, 8 end of an ear, 58 depth of trap, 59 energy function, 155 d-equivalence, 292 enumeration, 29 Desargues geometry, 258 equivalence, 292 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80230-7 - Topics in Topological Graph Theory Edited by Lowell W. Beineke and Robin J. Wilson Index More information Index 343 equivalent representations, 154 geometrical crossing number, 316 equivalent rotation systems, 24 geometrical graph, 328 Euler characteristic, 14, 21 geometrical thickness, 326 Euler genus, 64, 107, 226 girth of a graph, 3 Euler genus problem, 75 good drawing, 171, 314 Euler’s formula, 11, 14, 21 graph, 1, 19 Eulerian graph, 3 graph drawing, 63, 151 Eulerian trail, 3 graph minor, 31 even component, 36 Graph Minors Project, 81 evenly embedded graph, 115 graph nodal domain theorem, 157 excluded minor, 69 graph on a surface, 14 exponential growth, 300 graph representation, 153 extended edge-symbol, 310 grid, 82 Grötzsch’s theorem, 124 group of a transversal design, 269 face, 11, 14, 20, 164 growth degree, 300 face boundary walk, 20 Grünbaum colouring, 323 face-transitive map, 305 face-width, 117, 324 factorization, 213 Hajós join, 114 faithful action, 24 Halin graph, 322 Fano plane, 174, 245 Hamiltonian graph, 3 Fáry’s theorem, 152 handle, 12 fibre, 28, 292, 328 Heawood map colour problem, 23, finite projective plane, 247, 250 63, 112 finite-connectivity, 295 Heawood number, 23 flag, 25, 163, 174, 203, 264 Heffter’s first difference problem, 282 flag graph, 165 hereditary, 318 flag-simple, 164 high-end colouring, 113 flat type, 24 homeomorphic graphs, 8 flow, 323 homeomorphically irreducible tree, 322 F -map, 205 homogeneous representation, 176 fold number, 328 Hurwitz system, 191 forbidden family, 17 Hurwitz’s theorem, 232 forbidden subgraph, 69 force-directed placement, 160 forest, 4 four-colour theorem, 22, 322 immersion of a graph, 138 fragment, 297 incidence geometry, 174 framework, 177 incidence relation, 174 fullerene, 156 incidence structure, 174 fundamental polygon, 172 incident vertex and edge, 2 independence ratio, 117 independent diagonal curve, 122 general rotation system, 24 independent odd crossing number, 136 generalized Laplacian, 156 induced subgraph, 7 generalized Petersen graph, 143 infinite-connectivity, 296 generalized pseudosurface, 248 inserting an edge, 35 generalized quadrangle, 262 integer-length edge, 328 generic iterative graph representation algorithm, intermediate growth, 300 162 intersecting line segments, 329 genus, 15, 20 irredundant generating set, 236 genus distribution polynomial, 46 isolated vertex, 2 genus of a geometry, 249 isomorphic branched coverings, 191 genus of a group, 28, 225 isomorphic coverings, 182 genus problem, 75 isomorphic graphs, 2, 22 geodesic, 332 isomorphism of embeddings, 22 geodetic edge, 306 isomorphism of graphs, 2, 22 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80230-7 - Topics in Topological Graph Theory Edited by Lowell W. Beineke and Robin J. Wilson Index More information 344 Index join, 2 locally planar embedding, 113 join of graphs, 6 loop, 1 JW group, 241 low-end colouring, 116 k-choosable graph, 126 map, 163 k-chromatic graph, 9 map automorphism, 201, 305 k-colourable graph, 9 map colour problem, 317 k-colour-critical graph, 114 map colour theorem, 16 k-connected graph, 9, 100 map on a surface, 22 k-crossing-critical graph, 139 map theory, 22 k-degenerate graph, 126 Maschke’s characterization, 235 k-dimensional tree, 4 maximum crosscap number, 20, 47 k-edge-colourable graph, 9 maximum genus, 20, 34, 46 k-edge-connected graph, 9 medial map, 167, 221 k-flow, 323 Mendelsohn triple system, 260, 270 K-graph, 71 Menger graph, 248 k-grid, 82 Menger’s theorem, 9 meridian, 122 Kirchhoff’s current law, 281 M Kirkman triple system, 260 -flag simple map, 164 k-list-colourable graph, 126 minimal forbidden minor, 69 k-regular graph, 2 minimal forbidden subgraph, 69 k-separation, 69 minimum crosscap number, 20, 47 k-tree, 4 minimum genus, 20, 46 Klein bottle, 12 minor, 8, 31, 69, 82 minor ordering, 318 Kuratowski’s theorem, 11, 64 minor-closed family, 331 Kuratowski-type theorem, 38 minor-minimal forbidden family, 17 mixed type, 309 Möbius function, 185 ladder, 48 Möbius strip, 12 Laplace method, 156 monodromy group, 24, 25, 200 Laplacian, 156 morphism of maps, 201 large edge-width embedding, 331 multiple edges, 1 lattice, 301 leapfrog transformation, 169 ledge numbers, 216 natural projection, 28 left action of a group, 24 necklace, 5, 38, 56 left regular representation, 182 negative support, 157 length of walk, 3 neighbour, 2 Levi graph, 165, 174, 248 neighbourhood, 2, 181 LEW embedding, 331 neighbourhood graph, 270 LEW weight function, 331 neighbourhood system, 292 lexicographic product, 6 never-increasing sequence, 95 lifting an embedding, 29 non-degenerate representation, 153 line of an incidence structure, 174 non-orientable genus, 16, 226, 317 lineal incidence structure, 174 non-orientable genus distribution, 47 linear crossing number, 316 non-orientable genus problem, 75 linear drawing, 316 non-orientable surface, 12 linear genus, 172 non-separable graph, 8 linear growth, 300 normalized assignment, 183 linear thickness, 326 nowhere-zero flow, 323 linked decomposition, 89 number of embeddings, 46, 47 linked edges, 94 list-colourable graph, 126 local rotation, 315 obstruction, 63, 318 locally bipartite embedded odd component, 36 graph, 115 odd crossing number, 136 locally finite graph, 289 one-way infinite path, 290 © Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-80230-7 - Topics in Topological Graph Theory Edited by Lowell W.
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