Báo cáo toán học: " Cyclic Sieving Phenomenon in Non-Crossing Connected Graphs" pps
... 10.1]. 6.1 Cyclic sieving phenomenon in other types of graphs In [3], one finds various formulas f or counting classes of non-crossing graphs, of which (1) is one. Consider the following four generating ... let C be the cyclic g roup of order n acting on X by rotation. Then (X, X(q), C) exhibits the cyclic sieving phenomen o n. 6.2 Unifying algebraic proof of cyclic sievin...
Ngày tải lên: 08/08/2014, 12:23
... having at most 100 points. 9 Concluding remarks. 9.1. Classical Seidel’s switching is certainly the first origin of this paper. It goes back to the paper [vLinS66]. Explicitly the notion was introduced ... purpose we were using the following functions from COCO: ind, cgr, inm, sub,andaut. We describe below each of these functions. • ind input1.gen input2 output1.gen output2.map Starting from p...
Ngày tải lên: 07/08/2014, 07:21
... Cambridge, 2002 (Chapter 6). [RSW] V. Reiner, D. Stanton and D. White: The cyclic sieving phenomenon, J. Combin. Theory Ser. A 108 (2004), no. 1, 17–50. [Rh] B. Rhoades: Cyclic sieving, promotion, and representation ... expressible as X(q) = x∈X q s(x) , where s is an intrinsically defined statistic for the elements of X. Indeed, nearly all known instances of the cyclic sieving...
Ngày tải lên: 08/08/2014, 12:22
Báo cáo toán học: " Long heterochromatic paths in edge-colored graphs" potx
... vertices are joined by an edge if and only if they differ in exactly one coordinate or they differ in all coordinates. An edge is in color j (1 ≤ j ≤ k − 1) if and only if its two ends differ in exactly ... Tuza, Rainbow Hamiltonian paths and canonically colored sub- graphs in infinite complete graphs, Mathematica Pannonica 1 (1990), 5–13. [7] P. Erd˝os and Zs. Tuza, Rainbow subgraphs...
Ngày tải lên: 07/08/2014, 13:21
Báo cáo toán học: "Geodetic topological cycles in locally finite graphs" docx
... endpoints x, y. As C is closed, every point in P \ C is contained in a C-arc in P. Suppose no C-arc in P is a shortcut of C. We can find a family (W i ) i∈N of countably many internally disjoint ... disjoint arcs in P , such that fo r every i, W i is either a C-arc or an arc cont ained in C, and every edge in P lies in some W i (there may, however, exist ends in P that are no...
Ngày tải lên: 08/08/2014, 01:20
Báo cáo toán học: "On winning fast in Avoider-Enforcer games" pps
... vertices. A connected graph is called biconnected, if it remains connected after the removal of any vertex. A biconnected component of a graph is a maximal biconnected subgraph. In particular, a single ... cent to v 1 in Avo ider’s graph at this point. For 2 i k, in the beginning of the i- t h subphase, Avoider chooses the vertex v i ∈ V i−1 of minimal degree in Enfor cer’s gr...
Ngày tải lên: 08/08/2014, 12:22
Báo cáo toán học: "Loose Hamilton Cycles in Random Uniform Hypergraphs" pps
... partitioned into 2m cells X x , x ∈ X of d points. Analogously Y is represented as dκm points partitioned into 2κm cells Y y , y ∈ Y of d/2 points. To construct Λ d we take a random pairing of X into ... and (ii) g(x, y) < 0 for all points in {(x, y) ∈ ∂T : y ≤ 1/2(3 + 2κ)}. Solving the equation ∂g ∂y (x, y) = 0 for x, noting that the equation is linear in x, we obtain x = y(1 − y) ((d...
Ngày tải lên: 08/08/2014, 12:23
Báo cáo toán học: "Steiner triple systems and existentially closed graphs" ppsx
... points. Then there exists a block that is disjoint from X . Proof. Let y be a point in the STS(v) which is not in X . Then, since v ≥ 19, there exist at least nine blocks containing y and, since ... removing a point and all the blocks containing it; in this case a point of degree at most 4. What remains is a configuration containing 17 or more triples on 12 or fewer points, again 5-spars...
Ngày tải lên: 07/08/2014, 13:21
Báo cáo toán học: "On oriented arc-coloring of subcubic graphs" ppsx
... the arcs outgoing from v) and the incoming color set of v (i.e. the set of colors of the arcs incoming to v), respectively. The drawing conventions for a configuration are the following: a vertex ... good QR 7 -arc-coloring of H. Suppose now that H 1 contains a special cycle C. The graph H 1 contains three 2- vertices. Since a special cycle consists in k pairs of 2-sources and 2-sinks, C...
Ngày tải lên: 07/08/2014, 13:21
Báo cáo toán học: "Fractional biclique covers and partitions of graphs" ppsx
... isolated ones in A corresponds to a matching in G with the property that the subgraph induced by the matching is K 2,2 -free. This implies that the edges of the matching cannot be in any biclique ... and biclique coverings and factorizations of (0, 1)-matrices, Bulletin of the I.C.A. 14 (1995) 17-86. [16] J. Orlin, Contentment in graph theory: covering graphs with cliques, Indag. Math...
Ngày tải lên: 07/08/2014, 13:21