I am a professor in the University of Costa Rica. I completed my Ph.D at Central European University/Renyi Institute in Budapest, under the supervision of Ervin Győri in 2020. I obtained my bachelor's degree at the Universidad de Costa Rica in 2015. Before starting the Ph. D program I spend seven months as a visiting student at the Institute of Pure and Applied Mathematics (IMPA) in Rio de Janeiro (Here is my CV).
I am regularly collaborating with Mathematical Competitions projects for Undergraduate students at Universidad de Costa Rica. (web page: Equipo de Competencias Universitarias de Matemáticas UCR, in Spanish)
Google Schoolar Profile https://scholar.google.com/citations?hl=en&user=leE-yR0AAAAJ
The Main focus of my research is Extremal Graph and Hypergraph Theory. In particular I am interested in Turán type problems and Berge Hypergraphs. I am also interested in Ramsey Theory, Extremal Set Theory, and applications of Probabilistic and Algebraic Methods in Combinatorics.
E. Győri, A. Paulos, N. Salia, C. Tompkins, O. Zamora. The Maximum Number of Pentagons in a Planar Graph. Journal of Graph Theory 108.2 (2025): 229-256.
E. Győri, N. Salia, C. Tompkins, O. Zamora. Turán numbers of Berge trees. Discrete Mathematics 346.4 (2023): 113286.
D. Ghosh, E. Győri, A. Paulos, C. Xiao, O. Zamora. Planar Turán Number of the ϴ_6. Studia Scientiarum Mathematicarum Hungarica 61.2 (2024): 89-115.
E. Győri, A. Paulos, O. Zamora. The Minimum Number of 4-Cycles in a Maximal Planar Graph with Small Number of Vertices. Bulletin of the Iranian Mathematical Society 49.5 (2023): 61.
D. Ghosh, E. Győri, A. Paulos, C. Xiao, O. Zamora. The Turán Number of the Triangular Pyramid of 3-Layers. Discrete Applied Mathematics 317 (2022): 75-85.
E. Győri, N. Salia, C. Tompkins, O. Zamora. Inverse Turán numbers. Discrete Mathematics 345.5 (2022): 112779.
A. Grzesik, E. Győri, A. Paulos, N. Salia, C. Tompkins, O. Zamora. The Maximum Number of Paths of Length Three in a Planar Graph. Journal of Graph Theory 101.3 (2022): 493-510.
E. Győri, A. Paulos, N. Salia, C. Tompkins, O. Zamora. Generalized Planar Turán Numbers. Electronic Journal of Combinatorics, 26, no. 4 (2021) P4-32.
C. Xiao, O. Zamora. A note on the Turán number of disjoint union of wheels. Discrete Mathematics 344, no. 11 (2021): 112570.
D. Gosh, E. Győri, O. Janzer, A. Paulos, N. Salia, O. Zamora. The maximum number of induced C5's in a planar graph. Journal of Graph Theory 99.3 (2022):378-398.
C. Xiao, G. Katona, J. Xiao, O. Zamora. The Turán number of the square of a path. Discrete Applied Mathematics volume 307 (2022).
E. Győri, N. Salia, O. Zamora. Connected Hypergraphs without long Berge paths. European Journal of Combinatorics, 96 (2021): 103353.
G. Damásdi, B. Keszegh, D. Malec, C. Tompkins, Z. Wang, O. Zamora. Saturation problems in the Ramsey theory of graphs, posets and point sets, European Journal of Combinatorics 95 (2021): 103321.
D. Ghosh, E. Győri, R. R. Martin, A. Paulos, N. Salia, C. Xiao, O. Zamora. The Maximum Number of Paths of Length Four in a Planar Graph, Discrete Mathematics 344, no. 5 (2021): 112317.
D. Ghosh, E. Győri, A. Paulos, N. Salia, O. Zamora. The Maximum Wiener Index of Maximal Planar Graphs, Journal of Combinatorial Optimization volume 40, 1121-1135 (2020).
E. Győri, N. Lemons, N. Salia, O. Zamora. The Structure of Hypergraphs without long Berge cycles, Journal of Combinatorial Theory, Series B (2020).
B. Ergemlidze, E. Győri, A. Methuku, N. Salia, C. Tompkins, O. Zamora. Avoiding long Berge cycles, the missing cases k =r+1 and k=r+2, Combinatorics, Probability and Computing, 1-13, (2019).
N. Salia, C. Tompkins, Z. Wang, O. Zamora. Ramsey numbers of Berge-hypergraphs and related structures, Electronic Journal of Combinatorics, 26, no. 4 (2019) P4-40.
E. Győri, N. Salia, C. Tompkins, O. Zamora. The maximum number of P_l copies in P_k-free graphs, Discrete Mathematics and Theoretical Computer Science 21 (2019) #14.
N. Salia, C. Tompkins, O. Zamora. An Erdős-Gallai type theorem for vertex colored graphs, Graphs and Combinatorics 35 (2019) 689–694.
José Antonio de la Peña and EMALCA Team. Sistemas de transporte en México: un análisis de centralidad en teoría de redes. Realidad, datos y espacio revista internacional de estadística y geografía Vol. 3 Num. 3 (2012) 72-91. This project was derived from the School of Mathematics of Latin American and the Caribbean (EMALCA), I was selected as part of the EMALCA Team.
B. Csaba, G. Collado, O. Zamora. Packing independent cliques into planar graphs. arXiv:2408.03298 (2024).
N. Salia, C. Spiegel, C. Tompkins, O. Zamora. Independent Chains in Acyclic Posets. arXiv:1912.03288 (2019).
Seminario de Resolución de Problemas 2019. A compilation of Problems for the Problem Solving Seminar at Universidad de Costa Rica.
Seminario de Resolución de Problemas 2020. A compilation of Problems for the Problem Solving Seminar at Universidad de Costa Rica.