English
Related papers

Related papers: The 3x+1 Semigroup

200 papers

The $3x+1$ map $T$ is defined on the $2$-adic integers $\mathbb{Z}_2$ by $T(x)=x/2$ for even $x$ and $T(x)=(3x+1)/2$ for odd $x$. It is still unproved that under iteration of $T$ the trajectory of any rational $2$-adic integer is eventually…

Number Theory · Mathematics 2021-02-01 Josefina López , Peter Stoll

The $3x+k$ function $T_{k}(n)$ sends $n$ to $(3n+k)/2$ resp. $n/2,$ according as $n$ is odd, resp. even, where $k \equiv \pm 1~(\bmod \, 6)$. The map $T_k(\cdot)$ sends integers to integers, and for $m \ge 1$ let $n \rightarrow m$ mean that…

Complex Variables · Mathematics 2015-10-27 Jason P. Bell , Jeffrey C. Lagarias

We propose the existence of an infinite class of exact analogues of the 3x+1 conjecture for rational numbers with fixed denominators. For some other denominators, there are several attracting cycles, which exhibit scaling and covariance…

Dynamical Systems · Mathematics 2007-05-23 Barry Brent

The (3x+1)-Map, T, acts on the set, Pi, of positive integers not divisible by 2 or 3. It is defined by T(x) = (3x+1)/2^k, where k is the largest integer for which T(x) is an integer. The (3x+1)-Conjecture asks if for every x in Pi there…

Number Theory · Mathematics 2007-05-23 Alex V. Kontorovich , Yakov G. Sinai

This article discusses numerical semigroups having a generator which is as large as possible. This turns out to be $2g+1$, where $g$ is the genus of the semigroup. We will show that these semigroups are closely related to symmetric…

Group Theory · Mathematics 2026-04-27 Michael Hellus , Reinhold Hübl , Anton Rechenauer

In this paper we confirm a conjecture of Sun which states that each positive integer is a sum of a square, an odd square and a triangular number. Given any positive integer m, we show that p=2m+1 is a prime congruent to 3 modulo 4 if and…

Number Theory · Mathematics 2009-02-07 Byeong-Kweon Oh , Zhi-Wei Sun

The notion of (3+1)-avoidance has shown up in many places in enumerative combinatorics. The natural goal of enumeration of all (3+1)-avoiding posets remains open. In this paper, we enumerate graded (3+1)-avoiding posets for both reasonable…

Combinatorics · Mathematics 2015-10-15 Joel Brewster Lewis , Yan X Zhang

We study triples {a,b,c} of distinct nonzero rational numbers such that a+1,b+1,c+1,ab+1,ac+1,bc+1 and abc+1 are all perfect squares. We prove that there exist infinitely many such triples. In contrast, we show that no triple of positive…

Number Theory · Mathematics 2026-04-13 Andrej Dujella , Matija Kazalicki , Vinko Petričević

The 3x+1 problem is a difficult conjecture dealing with quite a simple algorithm on the positive integers. A possible approach is to go beyond the discrete nature of the problem, following M. Chamberland who used an analytic extension to…

Dynamical Systems · Mathematics 2014-02-11 Nik Lygeros , Olivier Rozier

A poset is (3+1)-free if it does not contain the disjoint union of chains of length 3 and 1 as an induced subposet. These posets play a central role in the (3+1)-free conjecture of Stanley and Stembridge. Lewis and Zhang have enumerated…

Combinatorics · Mathematics 2015-12-31 Mathieu Guay-Paquet , Alejandro H. Morales , Eric Rowland

The Collatz Conjecture (also known as the 3x+1 Problem) proposes that the following algorithm will, after a certain number of iterations, always yield the number 1: given a natural number, multiply by three and add one if the number is odd,…

Number Theory · Mathematics 2020-01-28 Matt Hohertz , Bahman Kalantari

Much work has been done attempting to understand the dynamic behaviour of the so-called "3x+1" function. It is known that finite sequences of iterations with a given length and a given number of odd terms have some combinatorial properties…

Number Theory · Mathematics 2016-11-21 Olivier Rozier

The 3X+1 function T(n) is (3n+1)/2 if n is odd and n/2 if n is even. The total stopping time \sigma_\infty (n) for a positive integer n is the number of iterations of the 3x+1 function to reach 1 starting from n, and is \infty if 1 is never…

Number Theory · Mathematics 2007-05-23 David Applegate , Jeffrey C. Lagarias

Taking a new approach towards analyzing the Collatz Problem, or, 3x+1 conjecture. Introducing some new functions, the Collatz-2 and Collatz-3 sequences, as well as deducing results related to Collatz-2 and Collatz-3 sequences.

General Mathematics · Mathematics 2008-04-24 Roupam Ghosh

In the paper, some special linear combinations of the terms of rational cycles of generalized Collatz sequences are studied. It is proved that if the coefficients of the linear combinations satisfy some conditions then these linear…

Number Theory · Mathematics 2025-10-02 Yagub N. Aliyev

An integer of the form $T_x=\frac{x(x+1)}2$ for some positive integer $x$ is called a triangular number. A ternary triangular form $aT_{x}+bT_{y}+cT_{z}$ for positive integers $a,b$ and $c$ is called regular if it represents every positive…

Number Theory · Mathematics 2019-03-11 Mingyu Kim , Byeong-Kweon Oh

We introduce the notion of numerical semigroups generated by concatenation of arithmetic sequences and show that this class of numerical semigroups exhibit multiple interesting behaviours.

Commutative Algebra · Mathematics 2020-03-27 Ranjana Mehta , Joydip Saha , Indranath Sengupta

We study numerical semigroups with the property "multiplicity= embedding dimension+1", generated by concatenation of arithmetic sequences.

Commutative Algebra · Mathematics 2020-03-27 Ranjana Mehta , Joydip Saha , Indranath Sengupta

A rational Diophantine $m$-tuple is a set $\{a_1,\ldots,a_m\}$ of distinct nonzero rational numbers such that $a_i a_j+1$ is a square for all $1\leq i < j\leq m$. Similarly, we may ask when $a_ia_j+1$ is a $k$-th power. Here, we study the…

Number Theory · Mathematics 2026-05-04 Alen Andrašek

The $3x+1$ problem, also called the Collatz conjecture, is a very interesting unsolved mathematical problem related to computer science. This paper generalized this problem by relaxing the constraints, i.e., generalizing this deterministic…

Computational Complexity · Computer Science 2013-11-25 Bojin Zheng , Yangqian Su , Hongrun Wu , Li Kuang