BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Muxi Li DTSTART:20260603T073000Z DTEND:20260603T090000Z DTSTAMP:20260604T142404Z UID:Mos-Bei-top-seminar/145 DESCRIPTION:Title: A Weak Solution of Inverse Treblecross: Periodicity\, Charac teristic Functions\, and Teaching Practice\nby Muxi Li as part of Mosc ow-Beijing topology seminar\n\n\nAbstract\nThis talk delves into the mathe matical solving of an 1D impartial avoidance game we named "Inverse Treble cross"\, adapted from the game "Treblecross" introduced by Berlekamp\, Con way and Guy in their famous work "Winning Ways for Your Mathematical Plays ". For audiences new to Combinatorial Game Theory\, the presentation will begin with a gentle introduction to the Sprague-Grundy (SG) theorem and oc tal games. We will see how standard games neatly decompose into independen t subgames. However\, Inverse Treblecross is notoriously stubborn: placing a piece does not cleanly isolate the remaining empty spaces\, making it r emarkably difficult to evaluate.\nDespite this resistance\, we reveal a su rprising hidden order. By constructing specific characteristic functions a nd mapping board parities\, we demonstrate that the SG sequence for an emp ty board is ultimately confined to the values 0 and 1\, perfectly dictated by a modulo-10 rule.\nIn general\, the topic of combinatorial game theory also plays an important role in mathematics education. I will conclude th e talk by sharing how relevant topics originated and evolved through teach ing practices. No prior knowledge of Combinatorial Game Theory is required . The talk will be self-contained and accessible to a general math audienc e.\n LOCATION:https://researchseminars.org/talk/Mos-Bei-top-seminar/145/ END:VEVENT END:VCALENDAR