At #Integers2025 this spring, I collaborated with a new group and proved that Misere Partizan Arc Kayles is PSPACE-complete. That paper just went up on the arXiv: https://arxiv.org/abs/2511.21888

For that paper we implemented two new playable games: Misere Partizan Arc Kayles itself (https://kyleburke.info/DB/combGames/miserePartizanArcKayles.html) and a Normal-Play version of Bounded Constraint Logic (https://kyleburke.info/DB/combGames/normalBoundedConstraintLogic.html).

I'm especially excited about how clearly we talked about using Constraint Logic to provide computational hardness.

#CombinatorialGames #PSPACEComplete

Misère Partizan Arc Kayles is PSPACE-complete, even on Planar Graphs

We show that Misère Partizan Arc Kayles is PSPACE-complete on planar graphs via a reduction from Bounded Two-Player Constraint Logic. Furthermore, we show how to embed our gadgets onto the square and triangular grids. In order to clearly explain these results, we get into the details of Bounded Two-Player Constraint Logic and find three PSPACE-complete variants of that as well.

arXiv.org

Gamesters at conferences play games. #Red7 at lunch on the final day (day 4) of #Integers2025.

This was a great conference and a real blast to be a part of! Thanks to Bruce and all the organizers for letting me be a part of it.

On the way to #Integers2025 , I told my colleague, trapped in the car with me, that I was going to be lost in the #NumberTheory talks. I mused that all I remembered from abstract algebra that might be relevant was Cayley groups.

I didn't see that name (Cayley) until day three. I failed even at knowing what I wouldn't know.

Played #Red7 over lunch at #Integers2025. (I think I'm about to lose in the photo.)

The second day of #Integers2025 was excellent! I heard some great talks, especially one from Carrie Finch-Smith. Me and the other three gamesters I know about here also took some time and I think we found a game to be #PSPACE complete, so we're definitely going to be writing that up!

Tonight we got to see a tree that owns itself. Cool stuff!

The organizers have been totally awesome. Great conference so far!

#NumberTheory #CombinatorialGames

Day 1 of #Integers2025 just wrapped up! Integers is a #NumberTheory and #Combinatorics conference. There's historically a bit of CGT too. Here are my summaries of the #CombinatorialGames talks: https://combinatorialgametheory.blogspot.com/2025/05/integers-2025-cgt-talks.html

Two of the talks were the result of #UndergraduateResearch!

Integers 2025 CGT Talks

Combinatorial Game Theory blog. Algorithmic, computational complexity, CGT, abstract games, Nim, Col, Snort, Kayles.