Hierarchies of turing machines with restricted tape alphabet size
Oscar H. Ibarra,Sartaj Sahni +1 more
TLDR
It is shown that for any real constants b>a>=0, multitape Turing machines operating in space L"1(n)=[bn^r] can accept more sets than those operating inspace L"2( n)=[an^ r] provided the number of work tapes and tape alphabet size are held fixed.About:
This article is published in Journal of Computer and System Sciences.The article was published on 1975-08-01 and is currently open access. It has received 11 citations till now. The article focuses on the topics: Multitape Turing machine & NSPACE.read more
Citations
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Journal ArticleDOI
Relating refined space complexity classes
TL;DR: Noncontainment results for both nondeterministic and deterministic classes of both binary and unary languages are obtained.
Journal ArticleDOI
Techniques for separating space complexity classes
TL;DR: Diagonalization, cardinality, and recursive padding arguments are used to separate the Turing machine space complexity classes obtained by bounding space, number of worktape symbols, and number ofWorktape heads.
Journal ArticleDOI
Two-way automata and length-preserving homomorphisms
TL;DR: For two-way finite automata, the closure under length-preserving homomorphisms is much more powerful than nondeterminism, and two conjectures about the state-complexity of unary languages are disproved.
Journal ArticleDOI
Two-dimensional finite automata and unacceptable functions
Katsushi Inoue,Akira Nakamura +1 more
TL;DR: This note first introduces the concept of “functions acceptable by two-dimensional finite automata” and then gives several functions unacceptable by three-dimensional infinite automata.
Book ChapterDOI
Improved Time and Space Hierarchies of One-Tape Off-Line TMs
Kazuo Iwama,Chuzo Iwamoto +1 more
TL;DR: Improved time and space hierarchies of one-tape off-line Turing Machines (TMs) are presented, which substantially improves the Hartmanis and Stearns' (log t 1(n))-gap which survived more than 30 years.
References
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Book
Formal Languages and Their Relation to Automata
TL;DR: The theory of formal languages as a coherent theory is presented and its relationship to automata theory is made explicit, including the Turing machine and certain advanced topics in language theory.
Journal ArticleDOI
On the computational complexity of algorithms
Proceedings ArticleDOI
Hierarchies of memory limited computations
TL;DR: The computational complexity of binary sequences as measured by the rapidity of their generation by multitape Turing machines is investigated and a "translational" method which escapes some of the limitations of earlier approaches leads to a refinement of the established hierarchy.
Journal ArticleDOI
A Hierarchy Theorem for Polynomial-Space Recognition
TL;DR: It is shown that nondeterministic such machines with a read-only input and a single worktape operating within space are more powerful than those with m symbols.