parsimagma-greedy-cover: a refuter published on the SAIR Contributor Network

parsimagma-greedy-cover is now public on the SAIR Contributor Network, entered into the Mathematics Distillation Challenge Stage 2. It is a deterministic refuter with no LLM calls: given two equational laws it finds a finite magma satisfying the first and violating the second, and emits a Lean 4 certificate the organisers’ judge accepts under plain decide. The point of publishing is the ordering rather than the score — four instances of Z/2 refute 11,871,871 of the ETP’s 13,855,357 false implications, twenty-five refute 97.2%, and x ◇ y = 7x + 7y over Z/13 alone refutes 268 pairs that Vampire’s fmb, Mace4 and z3 on a ground encoding all fail to find. The honest number is on the item: 55 of 200 on the graded distribution, zero on the true half by design, and zero on the extra_hard category, which is selected against exactly this method.