Bernardo Subercaseaux is presenting how to use a SAT solver to prove that the you need (exactly) 15 colours to solve the packing colouring problem in a infinite grid! #TACAS #ETAPS 2023

Today's clause-sharing portfolio #SATSolving cannot produce UNSAT proofs, which makes it unsuitable whenever trusting a result is critical. This changes! In our paper just accepted at #TACAS 2023, #AWS-affiliated researchers (D. Michaelson, M. Heule, M. Whalen, B. Kiesl-Reiter) and I have derived a scalable approach based on LRAT+CaDiCaL+Mallob producing efficiently verifiable proofs, with some interesting distributed algorithms and showing good performance on up to 800 cores. More coming soon!