3 research outputs found

    Bounded-Depth Frege Complexity of Tseitin Formulas for All Graphs

    Get PDF
    We prove that there is a constant K such that Tseitin formulas for an undirected graph G requires proofs of size 2tw(G)Ω(1/d) in depth-d Frege systems for d < (Formula presented.) where tw(G) is the treewidth of G. This extends Håstad recent lower bound for the grid graph to any graph. Furthermore, we prove tightness of our bound up to a multiplicative constant in the top exponent. Namely, we show that if a Tseitin formula for a graph G has size s, then for all large enough d, it has a depth-d Frege proof of size 2tw(G)O(1/d)poly(s). Through this result we settle the question posed by M. Alekhnovich and A. Razborov of showing that the class of Tseitin formulas is quasi-automatizable for resolution

    Bounded-depth Frege complexity of Tseitin formulas for all graphs

    Get PDF
    We prove that there is a constant K such that Tseitin formulas for a connected graph G requires proofs of size 2tw(G)javax.xml.bind.JAXBElement@531a834b in depth-d Frege systems for [Formula presented], where tw(G) is the treewidth of G. This extends Håstad's recent lower bound from grid graphs to any graph. Furthermore, we prove tightness of our bound up to a multiplicative constant in the top exponent. Namely, we show that if a Tseitin formula for a graph G has size s, then for all large enough d, it has a depth-d Frege proof of size 2tw(G)javax.xml.bind.JAXBElement@25a4b51fpoly(s). Through this result we settle the question posed by M. Alekhnovich and A. Razborov of showing that the class of Tseitin formulas is quasi-automatizable for resolution

    Bounded-Depth Frege Complexity of Tseitin Formulas for All Graphs

    No full text
    We prove that Tseitin formulas Ts(G)Ts(G) for an undirected graph GG, requires proofs of size 2tw(G)Ω(1/d)2^{tw(G)^{\Omega(1/d)}} in depth d-Frege systems for d<Klogn/loglognd<{K \log n}/{\log \log n}, where tw(G)tw(G) is the treewidth of GG and KK a constant. This extends H\r{a}stad recent lower bound for the grid graph to any graph. Furthermore, we prove tightness of our bound up to a multiplicative constant in the top exponent. The talk is based on a joint work with Dmitry Itsykson, Artur Ryazonov, Anastasia Sofronova.Non UBCUnreviewedAuthor affiliation: Università degli Studi di Roma La SapienzaFacult
    corecore