English
Related papers

Related papers: The intricate labyrinth of Collatz sequences

200 papers

Using $p$-adic numbers, we partially categorize the cycles of a sizable class of polynomial dynamical systems. In turn, we prove a few results related to the non-trivial cycles of the $\textit{Collatz map}$ $\text{Col} : \mathbb{Z}_+ \to…

Dynamical Systems · Mathematics 2021-03-24 Vinny Pagano

This article investigates integer sequences that partition the sequence into blocks of various lengths - irregular arrays. The main result of the article is explicit formulas for numbering of irregular arrays. A generalization of Cantor…

Combinatorics · Mathematics 2023-10-31 Boris Putievskiy

A recast of the standard residue-class analysis of the 3x+1 (Collatz) map in terms of two elementary operators on arithmetic progressions. The resulting calculus (i) splits any progression into its even and odd subsequences in a single…

General Mathematics · Mathematics 2025-06-25 Sebastian Angermund

In 1937, Lothar Collatz conjectured that the sequence generated by the rule $f(n)=3n+1$ for $n\in\mathbb{N}$ odd, $f(n)=n/2$ for $n\in\mathbb{N}$ even, starting in any positive integer $n$ produces $1$. This is equivalent to (1) there are…

General Mathematics · Mathematics 2017-06-28 Ivan Slapnicar

We study variants of the well-known Collatz graph, by considering the action of the 3n+1 function on congruence classes. For moduli equal to powers of 2, these graphs are shown to be isomorphic to binary De Bruijn graphs. Unlike the Collatz…

Number Theory · Mathematics 2013-11-11 Thijs Laarhoven , Benne de Weger

We reformulate the $3x+1$ conjecture by restricting attention to numbers congruent to $2$ (mod $3$). This leads to an equivalent conjecture for positive integers that reveals new aspects of the dynamics of the $3x+1$ problem. Advantages…

Number Theory · Mathematics 2020-09-24 Roger Zarnowski

We present a new method to obtain infinite Sidon sequences, based on the discrete logarithm. We construct an infinite Sidon sequence A, with A(x)= x^{\sqrt 2-1+o(1)}. Ruzsa proved the existence of a Sidon sequence with similar counting…

Number Theory · Mathematics 2013-05-16 Javier Cilleruelo

This article is based upon previous work by Sousa Ramos and his collaborators. They first prove that the existence of only one orbit associated with the Collatz conjecture is equivalent to the determinant of each matrix of a certain…

Combinatorics · Mathematics 2021-01-05 Louis Kauffman , Pedro Lopes

In this paper, we prove the conjecture that if there is an odd perfect number, then there are infinitely many of them.

Number Theory · Mathematics 2022-02-10 Jose Arnaldo Bebita Dris

Let $g$ be a map from the set of positive integers into itself defined as follows: Let $x$ be a positive integer. If $x$ is odd, then $g(x)=3x+1$, and if $x$ is even, then $g(x)=x/2$. The $3x+1$ conjecture, also called the Collatz…

General Mathematics · Mathematics 2021-11-24 J. Llibre , C. Valls

Ring puzzles are tessellations of the Euclidean plane respecting local constraints around vertices. Such puzzles may arise in geometric group theory, for example, as embedded flat planes in certain CAT(0) complexes of dimension 2. In the…

Combinatorics · Mathematics 2025-01-24 Sylvain Barré , Othmane Oukrid , Mikaël Pichot

Although 10^230 terms of Recaman's sequence have been computed, it remains a mystery. Here three distant cousins of that sequence are described, one of which is also mysterious. (i) {A(n), n >= 3} is defined as follows. Start with n, and…

We construct Steiner triple systems without parallel classes for an infinite number of orders congruent to $3 \pmod{6}$. The only previously known examples have order $15$ or $21$.

Combinatorics · Mathematics 2020-07-28 Darryn Bryant , Daniel Horsley

Paul Erdos claimed that mathematics is not yet ready to settle the 3x+1 conjecture. I agree, but very soon it will be! With the exponential growth of computer-generated mathematics, we (or rather our silicon brethrern) would have a shot at…

Combinatorics · Mathematics 2009-03-25 Doron Zeilberger

A sequence $\{z_n\}_{n\geq0}$ is called ratio log-convex in the sense that the ratio sequence $\{\frac{z_{n+1}}{z_n}\}_{n\geq0}$ is log-convex. Based on a three-term recurrence for sequences, we develop techniques for dealing with the ratio…

Combinatorics · Mathematics 2013-10-01 Bao-Xuan Zhu

A multipermutation with $k$ copies each of $1\ldots n$ is Carlitz if neighbours are different. We enumerate these objects for $k=2,3,4$ and derive recurrences. In particular, we prove and improve a conjectured recurrence for $k=3$, stated…

Combinatorics · Mathematics 2017-02-20 Henrik Eriksson , Alexis Martin

Given a finite nonempty sequence S of integers, write it as XY^k, where Y^k is a power of greatest exponent that is a suffix of S: this k is the curling number of S. The Curling Number Conjecture is that if one starts with any initial…

Combinatorics · Mathematics 2014-09-17 Benjamin Chaffin , John P. Linderman , N. J. A. Sloane , Allan R. Wilks

In this paper, we partially solve an open problem, due to J.C. Molluzzo in 1976, on the existence of balanced Steinhaus triangles modulo a positive integer $n$, that are Steinhaus triangles containing all the elements of…

Combinatorics · Mathematics 2016-03-31 Jonathan Chappelon

We explore the Collatz conjecture and its variants through the lens of termination of string rewriting. We construct a rewriting system that simulates the iterated application of the Collatz function on strings corresponding to mixed…

Logic in Computer Science · Computer Science 2023-01-03 Emre Yolcu , Scott Aaronson , Marijn J. H. Heule

We present four constructions of inversion sequences, and use them to compute the enumeration sequences of 24 classes of pattern-avoiding inversion sequences. This completes the enumeration of inversion sequences avoiding one or two…

Combinatorics · Mathematics 2025-11-25 Benjamin Testart