ゲスト：関口次郎（東京農工大名誉教授）、12/16-12/19 photo

セミナー・ワークショップ「幾何学における代数的・組み合わせ論的視点」
日時：令和７年１１月１９日（水）15:00-16:30
場所：金沢大学自然科学５号館第２講義室
講演者：篠原雅史（滋賀大学）
タイトル：A lattice conjecture for planar $k$-distance sets
アブストラクト：A finite subset in the plane is called a $k$-distance set if it has exactly $k$ distinct distances between two points of the set. A set is said to be optimal if it has the maximum cardinality among $k$-distance sets in the plane. Erd\H{o}s and Fishburn (1996) conjectured that optimal $k$-distance sets are subsets of the triangular lattice $L_\Delta$ for $k \ge 7$.

In this talk, we will classify optimal $k$-distance sets for small $k$. Furthermore, I will introduce a new conjecture related to the Erd\H{o}s-Fishburn conjecture and present several related examples.

Guest: Himadri Shekhar Chakraborty (Shahjalal University of Science & Technology, BANGLADESH), 9/8-10. photo

ゲスト：関口次郎（東京農工大名誉教授）、7/28-8/1 photo

ゲスト：関口次郎（東京農工大名誉教授）、6/23-26、photo