About me

Hi, I am Andy! I am a PhD student at Lund University in Lund, Sweden and University of Copenhagen in Copenhagen, Denmark.

I am a member of the Mathematical Insights into Algorithms for Optimization (MIAO) Group led by Jakob Nordström.

My interests are in combinatorial optimization with a focus on pseudo-Boolean optimization and certifying the correctness of combinatorial optimization solvers.

Interests

Graph Theory
Combinatorial Optimization
Proof Logging

Education

MSc in computer science, 2021
TU Chemnitz, Chemnitz, Germany
Thesis

BSc in computer science, 2018
TU Chemnitz, Chemnitz, Germany
Thesis

Publications

Pseudo-Boolean Reasoning About States and Transitions to Certify Dynamic Programming and Decision Diagram Algorithms

Emir Demirović, Ciaran McCreesh, Matthew J. McIlree, Jakob Nordström, Andy Oertel, Konstantin Sidorov

30th International Conference on Principles and Practice of Constraint Programming (CP 2024), 2024

PDF Software
Certifying Without Loss of Generality Reasoning in Solution-Improving Maximum Satisfiability

Jeremias Berg, Bart Bogaerts, Jakob Nordström, Andy Oertel, Tobias Paxian, Dieter Vandesande

30th International Conference on Principles and Practice of Constraint Programming (CP 2024), 2024

PDF Experimental data
Certified MaxSAT Preprocessing

Hannes Ihalainen, Andy Oertel, Yong Kiam Tan, Jeremias Berg, Matti Järvisalo, Magnus O. Myreen, Jakob Nordström

International Joint Conference on Automated Reasoning (IJCAR 2024), 2024

PDF (extended version) Code Experimental data
Certifying MIP-based Presolve Reductions for 0-1 Integer Linear Programs

Alexander Hoen, Andy Oertel, Ambros Gleixner, Jakob Nordström

21st International Conference on the Integration of Constraint Programming, Artificial Intelligence, and Operations Research (CPAIOR 2024), 2024

PDF Code
End-to-End Verification for Subgraph Solving

Stephan Gocht, Ciaran McCreesh, Magnus O. Myreen, Jakob Nordström, Andy Oertel, Yong Kiam Tan

38th Annual AAAI Conference on Artificial Intelligence (AAAI-24), 2024

PDF Poster CakePB (verified checker)
Graphs with many edge-colorings such that complete graphs are rainbow

Josefran de Oliveira Bastos, Hanno Lefmann, Andy Oertel, Carlos Hoppen, Dionatan Ricardo Schmidt

Discrete Applied Mathematics, 2023

Journal version of "Maximum number of \( r \)-edge-colorings such that all copies of \( K_k \) are rainbow"

Paper
Certified Core-Guided MaxSAT Solving

Jeremias Berg, Bart Bogaerts, Jakob Nordström, Andy Oertel, Dieter Vandesande

29th International Conference on Automated Deduction (CADE-29), 2023

PDF Code Slides SAT: Extended Reunion Slides NordConsNet 2023 Slides CADE-29
Certified CNF Translations for Pseudo-Boolean Solving

Stephan Gocht, Ruben Martins, Jakob Nordström, Andy Oertel

25th International Conference on Theory and Applications of Satisfiability Testing (SAT 2022), 2022

Best Paper Award at SAT 2022

PDF PDF IJCAI Code Data Slides SAT+SMT 2022 slides SAT+SMT 2022 video
Fast ultrametric matrix-vector multiplication

Tobias Hofmann, Andy Oertel

Preprint

PDF Code
Maximum number of \( r \)-edge-colorings such that all copies of \( K_k \) are rainbow

Josefran de Oliveira Bastos, Hanno Lefmann, Andy Oertel, Carlos Hoppen, Dionatan Ricardo Schmidt

LAGOS (Procedia Computer Science), 2021

PDF

Projects

VeriPB

Proof checker for proof logging methods using pseudo-Boolean reasoning for various combinatorial solving, optimization and enumeration algorithms.

Ultrametric matrix tools

This toolbox provides functions and data structures to construct and handle ultrametric matrices in Rust and Python.

Raspberry Pi RF gpiod port

Python module for sending and receiving 433/315MHz LPD/SRD signals with generic low-cost GPIO RF modules on a Raspberry Pi.

Contact

andy.oertel(at)cs.lth.se