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Post correspondence problem

The Post correspondence problem is an undecidable decision problem that was introduced by Emil Post in 1946. Because it is simpler than the halting problem and the Entscheidungsproblem it is often used in proofs of undecidability.

Variants, Proof sketch of undecidability & Definition of the problem

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Overview

Definition of the problem

Proof sketch of undecidability

Variants

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Map overview Semantic statistics

Post correspondence problem

Nodes31
Edges30
Triples52
Avg. degree1.94
Density0.064516
Components1

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Post correspondence problem

Top relations

related to Variants · 25
Post correspondence problem → Another, Group Problem, Groups, Halava, Hirvensalo, ICP, It, Many, More, Moreover, NP-complete, One, PCP, Post, Post's Correspondence Problem, Problem, Regular Post Embedding Problem, RNP, The, The Identity Correspondence Problem
related to External links · 21
Post correspondence problem → An Introduction, Chapter, Chomsky, Computation, Computer Science, Dong, Eitan, Gurari, Information Technology, JavaPost Correspondence Problem, Jing, National Conference, Online PHP Based PCP, PCP, PCP Instance, Post's Correspondence Problem, Solution, SolverPCP AT HOMEPCP, The, The Analysis
related to Alternative definition · 5
Post correspondence problem → An, Another, Post, This, We
is a · 1
Post correspondence problem → undecidable decision problem that was introduced by Emil Post in 1946

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Important terminology

problem post correspondence state displaystyle one solution pcp tape undecidable two match decidable symbol example whether string machine alphabet finite

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Post correspondence problemis aundecidable decision problem that was introduced by Emil Post in 19460.90text
Post correspondence problemrelated to Alternative definitionThis0.60section
Post correspondence problemrelated to Alternative definitionPost0.60section
Post correspondence problemrelated to Alternative definitionAnother0.60section
Post correspondence problemrelated to Alternative definitionWe0.60section
Post correspondence problemrelated to Alternative definitionAn0.60section
Post correspondence problemrelated to External linksEitan0.60section
Post correspondence problemrelated to External linksGurari0.60section
Post correspondence problemrelated to External linksAn Introduction0.60section
Post correspondence problemrelated to External linksTheory0.60section
Post correspondence problemrelated to External linksComputation0.60section
Post correspondence problemrelated to External linksChapter0.60section

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