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Linda Cook gave a talk on (1) the recognition algorithm for graphs with no long even holes and (2) the structure of graphs with no holes of length≠𝓁 at the Discrete Math Seminar

On August 17, 2021, Linda Cook from the IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar on (1) a polynomial-time algorithm to detect long even holes and (2) a structure of graphs with no holes of length≠𝓁 for a fixed 𝓁≥7. The title of her talk was “Two results on graphs with holes of restricted lengths“.

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Duksang Lee (이덕상) gave a talk on intertwining connectivities for vertex-minors and pivot-minors of graphs at the Discrete Math Seminar

On August 10, 2021, Duksang Lee (이덕상) from KAIST and IBS Discrete Mathematics Group gave a talk at the Discrete Math Seminar, showing that there are finitely many pivot-minor-minimal graphs preserving the rank connectivity between two fixed pairs of vertex sets. The title of his talk was “Intertwining connectivities for vertex-minors and pivot-minors“.

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Semin Yoo (유세민) gave a talk on an analogue of q-binomial coefficients at the Discrete Math Seminar

On July 20, 2021, Semin Yoo (유세민) from the University of Rochester gave a talk on an analogue of q-binomial coefficients, counting subspaces having the Euclidean quadratic form, and its applications at the Discrete Math Seminar. She will move to KIAS next month as a postdoc. The title of her talk was “Combinatorics of Euclidean spaces over finite fields“.

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Stefan Weltge gave an online talk at the Virtual Discrete Math Colloquium on a strongly polynomial-time algorithm for the integer linear program with bounded subdeterminants and two nonzeros per row

On July 14, 2021, Stefan Weltge from the Technical University of Munich gave an online talk at the Virtual Discrete Math Colloquium on an efficient algorithm to solve the Integer Linear Program defined by an integer matrix whose subdeterminants are bounded by a constant and that contains at most two nonzero entries in each row. The title of his talk was “Integer programs with bounded subdeterminants and two nonzeros per row“.

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Suil O (오수일) gave a talk on the existence of even and odd [a,b]-factors in h-edge-connected r-regular graphs in terms of eigenvalues at the Discrete Math Seminar

On July 6, 2021, Suil O (오수일) from SUNY Korea gave a talk at the Discrete Math Seminar on upper bounds of certain eigenvalues to guarantee the existence of an even or odd [a,b]-factor in h-edge-connected r-regular graphs. The title of his talk was “Eigenvalues and [a, b]-factors in regular graphs“.