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Let $n$ be a positive integer, and let $R$ be a (possibly infinite dimensional) finitely presented algebra over a computable field of characteristic zero. We describe an algorithm for deciding (in principle) whether $R$ has at most finitely…

Rings and Algebras · Mathematics 2007-05-23 Edward S. Letzter

We classify the completely integrable systems associated with classical root systems whose potential functions are meromorphic at an infinite point.

Mathematical Physics · Physics 2010-11-08 Toshio Oshima

Although there is a somewhat standard formalization of computability on countable sets given by Turing machines, the same cannot be said about uncountable sets. Among the approaches to define computability in these sets, order-theoretic…

Logic in Computer Science · Computer Science 2022-09-07 Pedro Hack , Daniel A. Braun , Sebastian Gottwald

We define a class of functions termed "Computable in the Limit", based on the Machine Learning paradigm of "Identification in the Limit". A function is Computable in the Limit if it defines a property P_p of a recursively enumerable class A…

Computational Complexity · Computer Science 2017-02-21 Antony Van der Mude

We describe a theory of finite sets, and investigate the analogue of Dedekind's theory of natural number systems (simply infinite systems) in this theory. Unlike the infinitary case, in our theory, natural number systems come in differing…

Logic · Mathematics 2008-08-08 J. P. Mayberry , Richard Pettigrew

Infinite time Turing machines extend the operation of ordinary Turing machines into transfinite ordinal time. By doing so, they provide a natural model of infinitary computability, a theoretical setting for the analysis of the power and…

Logic · Mathematics 2007-05-23 Joel David Hamkins

It is possible to enumerate all computer programs. In particular, for every partial computable function, there is a shortest program which computes that function. f-MIN is the set of indices for shortest programs. In 1972, Meyer showed that…

Logic · Mathematics 2007-05-23 Jason Teutsch

An infinite set is orbit-finite if, up to permutations of the underlying structure of atoms, it has only finitely many elements. We study a generalisation of linear programming where constraints are expressed by an orbit-finite system of…

Logic in Computer Science · Computer Science 2024-11-14 Arka Ghosh , Piotr Hofman , Sławomir Lasota

This paper provides a new and more direct proof of the assertion that a Turing computable function of the natural numbers is primitive recursive if and only if the time complexity of the corresponding Turing machine is bounded by a…

Formal Languages and Automata Theory · Computer Science 2025-10-22 Daniel G. Schwartz

Models of computation operating over the real numbers and computing a larger class of functions compared to the class of general recursive functions invariably introduce a non-finite element of infinite information encoded in an arbitrary…

Computational Complexity · Computer Science 2010-12-20 Hector Zenil

A first-order structure $M$ is said to have the infinite sunflower property if, for each $k \in \mathbb{N}_+$ and each structure $M' \cong M$ whose elements are $k$-sets, there is $S \subseteq M'$, $S \cong M$, such that $S$ is a sunflower:…

Combinatorics · Mathematics 2026-03-10 Rob Sullivan , Jeroen Winkel

Computational content encoded into constructive type theory proofs can be used to make computing experiments over concrete data structures. In this paper, we explore this possibility when working in Coq with chain complexes of infinite type…

Logic in Computer Science · Computer Science 2010-04-29 César Domínguez , Julio Rubio

We present the concept of the \emph{information efficiency of functions} as a technique to understand the interaction between information and computation. Based on these results we identify a new class of objects that we call…

Computational Complexity · Computer Science 2019-04-09 P. W. Adriaans

We extend in a natural way the operation of Turing machines to infinite ordinal time, and investigate the resulting supertask theory of computability and decidability on the reals. The resulting computability theory leads to a notion of…

Logic · Mathematics 2007-05-23 Joel David Hamkins , Andy Lewis

Generating trees are a useful technique in the enumeration of various combinatorial objects, particularly restricted permutations. Quite often the generating tree for the set of permutations avoiding a set of patterns requires infinitely…

Combinatorics · Mathematics 2007-05-23 Vince Vatter

Let $T$ be a complete theory of fields, possibly with extra structure. Suppose that model-theoretic algebraic closure agrees with field-theoretic algebraic closure, or more generally that model-theoretic algebraic closure has the exchange…

Logic · Mathematics 2023-06-28 Will Johnson , Jinhe Ye

Every function on a finite set defines an equivalence relation and, therefore, a partition called the kernel of the function. Automata such that every possible partition is the kernel of a word are called totally compatible. A…

Formal Languages and Automata Theory · Computer Science 2021-10-12 David Fernando Casas Torres

The present article is devoted to some examples of functions whose arguments represented in terms of certain series of the Cantor type.

Classical Analysis and ODEs · Mathematics 2021-01-05 Symon Serbenyuk

We study sunflowers within the context of finitely generated substructures of ultrahomogeneous structures. In particular, we look at bounds on how large a set system is needed to guarantee the existence of sunflowers of a given size. We…

Combinatorics · Mathematics 2023-10-25 Nathanael Ackerman , Mostafa Mirabi

A sunflower is a collection of distinct sets such that the intersection of any two of them is the same as the common intersection $C$ of all of them, and $|C|$ is smaller than each of the sets. A longstanding conjecture due to Erd\H{o}s and…

Combinatorics · Mathematics 2025-01-29 Dhruv Mubayi , Lujia Wang