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Related papers: Isolated d.c.e. degrees and $\Sigma_1$ induction

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First, we study recollement of a derived category of unbounded complexes of modules induced by a partial tilting complex. Second, we give equivalent conditions for P^{centerdot} to be a recollement tilting complex, that is, a tilting…

Rings and Algebras · Mathematics 2007-05-23 Jun-ichi Miyachi

The purpose of this paper is to introduce the concept of reflecting numbers to the realm of number theory and to classify reflecting numbers of certain types. For us, reflecting numbers are coming from congruent numbers, above congruent…

Number Theory · Mathematics 2022-07-07 Ya-Qing Hu

A set is autoreducible if it can be reduced to itself by a Turing machine that does not ask its own input to the oracle. We use autoreducibility to separate the polynomial-time hierarchy from polynomial space by showing that all…

Logic · Mathematics 2016-09-07 Harry Buhrman , Lance Fortnow , Leen Torenvliet , Dieter van Melkebeek

Let $D=(V,A)$ be a directed graph of order $n\geq 6$. Let $W$ be a subset of $V$ with $|W|\geq 6$. Suppose that every vertex of $W$ has degree at least $(3n-3)/2$ in $D$. Then for any integer partition $|W|=n_1+n_2$ with $n_1\geq 3$ and…

Combinatorics · Mathematics 2019-07-29 Hong Wang

Generic computability has been studied in group theory and we now study it in the context of classical computability theory. A set A of natural numbers is generically computable if there is a partial computable function f whose domain has…

Group Theory · Mathematics 2014-02-26 Carl G. Jockusch , Paul E. Schupp

Strongly quadrangular matrices have been introduced in the study of the combinatorial properties of unitary matrices. It is known that if a (0, 1)-matrix supports a unitary then it is strongly quadrangular. However, the converse is not…

Combinatorics · Mathematics 2008-07-17 Simone Severini , Ferenc Szöllősi

A tight alignment between the degree vector and the leading eigenvector arises naturally in networks with neutral degree mixing and the absence of local structures. Many real-world networks, however, violate both conditions. We derive…

Social and Information Networks · Computer Science 2026-03-18 Sreerag Puravankara , Vipin P. Veetil

Trees without vertices of degree $2$ are sometimes named topological trees. In this work, we bring forward the study of the inducibility of (rooted) topological trees with a given number of leaves. The inducibility of a topological tree $S$…

Combinatorics · Mathematics 2018-02-20 Audace Amen Vioutou Dossou-Olory , Stephan Wagner

We prove that, for every invertible horizontal-like map (i.e., H{\'e}non-like map) in any dimension, the sequence of the dynamical degrees is increasing until that of maximal value, which is the main dynamical degree, and decreasing after…

Complex Variables · Mathematics 2023-07-21 Fabrizio Bianchi , Tien-Cuong Dinh , Karim Rakhimov

We consider a class of tempered subordinators, namely a class of subordinators with one-dimensional marginal tempered distributions which belong to a family studied in [3]. The main contribution in this paper is a non-central moderate…

Probability · Mathematics 2020-11-05 Nikolai Leonenko , Claudio Macci , Barbara Pacchiarotti

We identify a notion of reducibility between predicates, called instance reducibility, which commonly appears in reverse constructive mathematics. The notion can be generally used to compare and classify various principles studied in…

Logic · Mathematics 2023-06-22 Andrej Bauer

The unit Euclidean distance degree and the generic Euclidean distance degree are two well-studied invariants of projective varieties. These quantities measure the algebraic complexity of nearest-point problems on a variety, and in many…

Algebraic Geometry · Mathematics 2026-05-14 Laurenţiu G. Maxim , Jose Israel Rodriguez , Botong Wang

A finite non-increasing sequence of positive integers $d = (d_1\geq \cdots\geq d_n)$ is called a degree sequence if there is a graph $G = (V,E)$ with $V = \{v_1,\ldots,v_n\}$ and $deg(v_i)=d_i$ for $i=1,\ldots,n$. In that case we say that…

Combinatorics · Mathematics 2021-01-08 Atabey Kaygun

Differentially Private Stochastic Gradient Descent (DPSGD) is widely utilized to preserve training data privacy in deep learning, which first clips the gradients to a predefined norm and then injects calibrated noise into the training…

Machine Learning · Computer Science 2024-05-29 Haichao Sha , Yang Cao , Yong Liu , Yuncheng Wu , Ruixuan Liu , Hong Chen

Recovering the underlying Directed Acyclic Graph (DAG) structures from observational data presents a formidable challenge, partly due to the combinatorial nature of the DAG-constrained optimization problem. Recently, researchers have…

Machine Learning · Computer Science 2025-03-26 Zhen Zhang , Ignavier Ng , Dong Gong , Yuhang Liu , Mingming Gong , Biwei Huang , Kun Zhang , Anton van den Hengel , Javen Qinfeng Shi

In this note we first study regular $\mathbb{Z}$-graded local rings. We characterize commutative noetherian regular $\mathbb{Z}$-graded local rings in similar ways as in the usual local case. Then, we characterize graded isolated…

Commutative Algebra · Mathematics 2025-08-11 Haonan Li , Quanshui Wu

Second-order topological insulators are crystalline insulators with a gapped bulk and gapped crystalline boundaries, but topologically protected gapless states at the intersection of two boundaries. Without further spatial symmetries, five…

Mesoscale and Nanoscale Physics · Physics 2017-12-20 Josias Langbehn , Yang Peng , Luka Trifunovic , Felix von Oppen , Piet W. Brouwer

Let $E\supseteq F$ be a field extension and $M$ a graded Lie algebra of maximal class over $E$. We investigate the $F$-subalgebras $L$ of $M$, generated by elements of degree $1$. We provide conditions for $L$ being either ideally…

Rings and Algebras · Mathematics 2023-11-14 Marina Avitabile , Norberto Gavioli , Valerio Monti

We describe the various types of singularities that can arise for second order rational mappings and we discuss the historical and present-day, practical, role the singularity confinement property plays as an integrability detector. In…

Mathematical Physics · Physics 2018-09-11 Basil Grammaticos , Alfred Ramani , Ralph Willox , Takafumi Mase

Topological insulators embody a new state of matter characterized entirely by the topological invariants of the bulk electronic structure rather than any form of spontaneously broken symmetry. Unlike the 2D quantum Hall or quantum…