English
Related papers

Related papers: There are no cycles in the $3n+1$ sequence

200 papers

Define $\theta(x)=(x-1)/3$ if $x\geq 1$, and $\theta(x)=2x/(1-x)$ if $x<1$. We conjecture that the orbit of every positive rational number ends in 0. In particular, there does not exist any positive rational fixed point for a map in the…

Number Theory · Mathematics 2010-10-19 Mohammad Javaheri

We give a generalization of Collatz conjecture or 3n+1 problem on 2-adic completion of Q. A isometric of $Q_2$ provides information on the average behavior of the firsts terms of the sequence according to the class of $u_0$ modulo $2^m$. A…

Number Theory · Mathematics 2016-07-11 Vincent Fleckinger , Ibrahim Abdoulkarim

The base sequences BS(n+1,n) are four sequences of $\pm1$ and lengths n+1,n+1,n,n with zero auto correlation. The base sequence conjecture states that BS(n+1,n) exists for all positive integers and has been verified for $n\le40$. We present…

Combinatorics · Mathematics 2026-02-06 Xu Wang , Jiayi Zhu

Define the \emph{Collatz map} $\mathrm{Col} : \mathbb{N}+1 \to \mathbb{N}+1$ on the positive integers $\mathbb{N}+1 = \{1,2,3,\dots\}$ by setting $\mathrm{Col}(N)$ equal to $3N+1$ when $N$ is odd and $N/2$ when $N$ is even, and let…

Probability · Mathematics 2022-02-17 Terence Tao

A Universal Cycle for t-multisets of [n]={1,...,n} is a cyclic sequence of $\binom{n+t-1}{t}$ integers from [n] with the property that each t-multiset of [n] appears exactly once consecutively in the sequence. For such a sequence to exist…

Combinatorics · Mathematics 2024-02-27 Glenn Hurlbert , Tobias Johnson , Joshua Zahl

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

In a previous article, we reduced the unsolved problem of the convergence of Collatz sequences, to convergence of Collatz sequences of odd numbers, that are divisible by 3. In this article, we further reduce this set to odd numbers that are…

Combinatorics · Mathematics 2020-01-07 Maya Mohsin Ahmed

Following up on earlier work, I suggest why there are no mappings to infinity under the Collatz conjecture, nor under other mappings of the generalization $3n+p$, where $p$ is odd.

Number Theory · Mathematics 2019-10-09 M. J. Wensink

Denote by r(n) the length of a shortest integer sequence on a circle containing all permutations of the set {1,2,...,n} as subsequences. Hansraj Gupta conjectured in 1981 that r(n) <= n^2/2. In this paper we confirm the conjecture for the…

Combinatorics · Mathematics 2010-09-28 Emmanuel Lecouturier , David Zmiaikou

Base sequences BS(n+1,n) are quadruples of {1,-1}-sequences (A;B;C;D), with A and B of length n+1 and C and D of length n, such that the sum of their nonperiodic autocorrelation functions is a delta-function. The base sequence conjecture,…

Combinatorics · Mathematics 2010-10-12 Dragomir Z. Djokovic

Set out here are some fundamental theories that may be regarded as newly discovered metamathematics of the odd integers in relation to the Collatz conjecture (also called the 3x+1 problem). Originally motivated by the requirement to invent…

General Mathematics · Mathematics 2015-03-19 Michael A. Idowu

We intend to contribute to the Collatz dynamics problem by seeking to analyze the Collatz conjecture from the tree of numbers sequences. First, we show numerically that the distribution of odd numbers has an initial transient, and proceeds…

General Mathematics · Mathematics 2023-05-26 Eduardo M. K. Souza

In 1975, P. Erd\"{o}s proposed the problem of determining the maximum number $f(n)$ of edges in a graph of $n$ vertices in which any two cycles are of different lengths. In this paper, it is proved that $$f(n)\geq n+32t-1$$ for…

Combinatorics · Mathematics 2007-05-23 Chunhui Lai

The no-(k+1)-in line problem seeks the maximum number of points that can be selected from an $n \times n$ square lattice such that no $k+1$ of them are collinear. The problem was first posed more than $100$ years ago for the special case…

Combinatorics · Mathematics 2025-08-12 Benedek Kovács , Zoltán Lóránt Nagy , Dávid R. Szabó

The Collatz conjecture, also known as the 3n+1 problem, is one of the most popular open problems in number theory. In this note, an algorithm for the verification of the Collatz conjecture is presented that works on a standard PC for…

Number Theory · Mathematics 2025-02-25 Andreas-Stephan Elsenhans

The Collatz conjecture, which posits that any positive integer will eventually reach 1 through a specific iterative process, is a classic unsolved problem in mathematics. This research focuses on designing an efficient algorithm to compute…

Mathematical Software · Computer Science 2025-07-02 Eyob Solomon Getachew , Beakal Gizachew Assefa

In 1963, Anton Kotzig famously conjectured that $K_{n}$, the complete graph of order $n$, where $n$ is even, can be decomposed into $n-1$ perfect matchings such that every pair of these matchings forms a Hamilton cycle. The problem is still…

Combinatorics · Mathematics 2025-10-03 Stefan Glock , Amedeo Sgueglia

We obtain some new upper bounds on the maximum number $f(n)$ of edges in $n$-vertex graphs without containing cycles of length four. This leads to an asymptotically optimal bound on $f(n)$ for a broad range of integers $n$ as well as a…

Combinatorics · Mathematics 2021-10-13 Jie Ma , Tianchi Yang

For $n=1,2,3,\ldots$ let $S_n$ be the sum of the first $n$ primes. We mainly show that the sequence $a_n=\root n\of{S_n/n}\ (n=1,2,3,\ldots)$ is strictly decreasing, and moreover the sequence $a_{n+1}/a_n\ (n=10,11,\ldots)$ is strictly…

Number Theory · Mathematics 2013-11-01 Zhi-Wei Sun

We introduce a full binary directed tree structure to represent the set of natural numbers, further categorizing them into three distinct subsets: pure odd numbers, pure even numbers, and mixed numbers. We adopt a binary string…

General Mathematics · Mathematics 2024-06-12 Jishe Feng
‹ Prev 1 3 4 5 6 7 10 Next ›