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Resolution with Symmetry Rule applied to Linear Equations

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 نشر من قبل Constantin Seebach
 تاريخ النشر 2021
  مجال البحث الهندسة المعلوماتية
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This paper considers the length of resolution proofs when using Krishnamurthys classic symmetry rules. We show that inconsistent linear equation systems of bounded width over a fixed finite field $mathbb{F}_p$ with $p$ a prime have, in their standard encoding as CNFs, polynomial length resolutions when using the local symmetry rule (SRC-II). As a consequence it follows that the multipede instances for the graph isomorphism problem encoded as CNF formula have polynomial length resolution proofs. This contrasts exponential lower bounds for individualization-refinement algorithms on these graphs. For the Cai-Furer-Immerman graphs, for which Toran showed exponential lower bounds for resolution proofs (SAT 2013), we also show that already the global symmetry rule (SRC-I) suffices to allow for polynomial length proofs.



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