1. Extremal Problems Involving the Two Largest Complementarity Eigenvalues of a Graph

   • Alberto Seeger
   • David Sossa

   Original Paper 28 October 2019 Pages: 1 - 25

   

2. Classification of Maximum Hittings by Large Families

   • Candida Bowtell
   • Richard Mycroft

   Original Paper 16 November 2019 Pages: 27 - 39

3. Asymptotically Almost Every 2r-Regular Graph Has an Internal Partition

   • Nathan Linial
   • Sria Louis

   Original Paper 27 November 2019 Pages: 41 - 50

   

4. Convex Grabbing Game of the Point Set on the Plane

   • Naoki Matsumoto
   • Tomoki Nakamigawa
   • Tadashi Sakuma

   Original Paper 02 January 2020 Pages: 51 - 62

   

5. Alternating Sign Matrices: Extensions, König-Properties, and Primary Sum-Sequences

   • Richard A. Brualdi
   • Geir Dahl

   Original Paper 18 November 2019 Pages: 63 - 92

   

6. Matching Extendability and Connectivity of Regular Graphs from Eigenvalues

   • Wenqian Zhang

   Original Paper 14 November 2019 Pages: 93 - 108

7. Chromatic Number of the Cyclic Graph of Infinite Semigroup

   • Sandeep Dalal
   • Jitender Kumar

   Original Paper 16 November 2019 Pages: 109 - 113

8. The Edge-Connectivity of Strongly 3-Walk-Regular Graphs

   • Rongquan Feng
   • Wenqian Zhang

   Original Paper 19 November 2019 Pages: 115 - 124

9. The Intersection of Two Vertex Coloring Problems

   • Angèle M. Foley
   • Dallas J. Fraser
   • Tom P. LaMantia

   Original Paper 14 December 2019 Pages: 125 - 138

   

10. The Number of Tournaments with the Minimum Number of Upsets

    • Ilhan Hacioglu
    • Nuri Sendil
    • Carlos M. da Fonseca

    Original Paper 02 January 2020 Pages: 139 - 151

    

11. Online Coloring a Token Graph

    • Kevin G. Milans
    • Michael C. Wigal

    Original Paper 17 December 2019 Pages: 153 - 165

    

12. Long Paths in Bipartite Graphs and Path-Bistar Bipartite Ramsey Numbers

    • Michitaka Furuya
    • Shun-ichi Maezawa
    • Kenta Ozeki

    Original Paper 21 December 2019 Pages: 167 - 176

13. Correction to: Extended Formulations for Independence Polytopes of Regular Matroids

    • Volker Kaibel
    • Jon Lee
    • Stefan Weltge

    Correction 16 December 2019 Pages: 177 - 179