Paper Info
Title
On the Density of Languages Accepted by Turing Machines and Other Machine Models.
Abstract
A language is dense if the set of all infixes (or subwords) of the language is the set of all words. Here, it is shown that it is decidable whether the language accepted by a nondeterministic Turing machine with a one-way read-only input and a reversal-bounded read/write worktape (the read/write head changes direction at most some fixed number of times) is dense. From this, it is implied that it is also decidable for one-way reversal-bounded queue automata, one-way reversal-bounded stack automata, and one-way reversal-bounded $k$-flip pushdown automata (machines that can flip their pushdowns up to $k$ times). However, it is undecidable for deterministic Turing machines with two 1-reversal-bounded worktapes (even when the two tapes are restricted to operate as 1-reversal-bounded pushdown stacks).
Year
DOI
Venue
2018
10.25596/jalc-2018-189
Journal of Automata, Languages and Combinatorics
Field
DocType
Volume
Discrete mathematics,Stack (abstract data type),Queue,Automaton,Decidability,Turing machine,Pushdown automaton,Non-deterministic Turing machine,Mathematics,Undecidable problem
Journal
23
Issue
ISSN
Citations 
1-3
Journal of Automata, Languages and Combinatorics, 23, 189-199, 2018
0
PageRank 
References 
Authors
0.34
7
2
Name
Order
Citations
PageRank
Oscar H. Ibarra1293.37
Ian McQuillan29724.72