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Related papers: A Necessary Condition on the Collatz Conjecture

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We show that there can be no algorithm to decide whether infinite recursively described acyclic aspherical 2-complexes are contractible. We construct such a complex that is contractible if and only if the Collatz conjecture holds.

Group Theory · Mathematics 2020-03-23 Ian J Leary

We show an iterated function of which iterates oscillate wildly and grow at a dizzying pace. We conjecture that the orbit of arbitrary positive integer always returns to 1, as in the case of Collatz function. The conjecture is supported by…

Number Theory · Mathematics 2024-10-02 David Barina

The Collatz conjecture asserts that repeatedly iterating $f(x) = (3x + 1)/2^{a(x)}$, where $a(x)$ is the highest exponent for which $2^{a(x)}$ exactly divides $3x+1$, always lead to $1$ for any odd positive integer $x$. Here, we present an…

General Mathematics · Mathematics 2019-07-18 Zenon B. Batang

We establish the exact overlaps conjecture for iterated functions systems on the real line with algebraic contractions and arbitrary translations.

Dynamical Systems · Mathematics 2020-01-15 Ariel Rapaport

This paper introduces prime holdout problems, a problem class related to the Collatz conjecture. After applying a linear function, instead of removing a finite set of prime factors, a holdout problem specifies a set of primes to be…

Number Theory · Mathematics 2023-07-19 Max Milkert , Alex Ruchti , Josiah Yoder

The Collatz map is defined for a positive even integer as half that integer, and for a positive odd integer as that integer threefold, plus one. The Collatz conjecture states that when the map is iterated the number one is eventually…

Combinatorics · Mathematics 2015-01-19 Michael Albert , Bjarki Gudmundsson , Henning Ulfarsson

Linear-constraint loops are programs whose transition relation is specified by a system of linear inequalities. The termination problem asks, given a loop, whether it admits an infinite computation. Decidability of termination remains open…

Logic in Computer Science · Computer Science 2026-05-15 Mishel Carelli

The Collatz sequence for a given natural number $N$ is generated by repeatedly applying the map $N$ $\rightarrow$ $3N+1$ if $N$ is odd and $N$ $\rightarrow$ $N/2$ if $N$ is even. One elusive open problem in Mathematics is whether all such…

General Mathematics · Mathematics 2019-11-11 Rafael Ruggiero

We introduce an infinite set of integer mappings that generalize the well-known Collatz-Ulam mapping and we conjecture that an infinite subset of these mappings feature the remarkable property of the Collatz conjecture, namely that they…

Number Theory · Mathematics 2008-10-30 M. Bruschi

The Collatz and $abc$ conjectures, both well known and thoroughly studied, appear to be largely unrelated at first sight. We show that assuming the $abc$ conjecture true is helpful to improve the lower bound of integers initiating a…

Number Theory · Mathematics 2025-10-22 Olivier Rozier

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

In the present paper, we are interested in classifying of Collatz sequences on based to the different behavior of these sequences when their lengths tend to infinity. A Collatz infinite sequence can be defined as an infinite ordered set of…

General Mathematics · Mathematics 2021-06-03 Raouf Rajab

In this paper we study the existence of continuous solutions and their constructions for a second order iterative functional equation, which involves iterate of the unknown function and a nonlinear term. Imposing Lipschitz conditions to…

Classical Analysis and ODEs · Mathematics 2018-03-13 Xiao Tang , Weinian Zhang

Pairs of consecutive integers have the same height in the Collatz problem with surprising frequency. Garner gave a conjectural family of conditions for exactly when this occurs. Our main result is an infinite family of counterexamples to…

Number Theory · Mathematics 2015-12-01 Marcus Elia , Amanda Tucker

The famous (3n + 1) or Collatz conjecture has admitted some progress over the last several decades towards the conclusion that the conjecture is true (i.e. that all Collatz sequences will eventually reach a value of one), but has stubbornly…

General Mathematics · Mathematics 2021-03-30 Brian Mohan Gurbaxani

For a matrix $A$ which satisfies Crouzeix's conjecture, we construct several classes of matrices from $A$ for which the conjecture will also hold. We discover a new link between cyclicity and Crouzeix's conjecture, which shows that…

Functional Analysis · Mathematics 2024-01-01 Ryan O'Loughlin , Jani Virtanen

In this paper, we discuss the well known 3x+1 conjecture in form of the accelerated Collatz function T defined on the positive odd integers. We present a sequence of quotient spaces and an invertible map that are intrinsically related to…

Number Theory · Mathematics 2016-07-26 Peter Hellekalek

Consider a finite positive integer. If it is even, divide it by 2, and if it is odd, multiply it by 3 and add 1. This will give you a new integer. Following the procedure for the new integer, you will receive another integer. Repeat the…

General Mathematics · Mathematics 2021-05-26 Hassan Rezai Soleymanpour

I show here that there are three different kinds of iterations for the reduced Collatz algorithm; depending on whether the root of the number is odd or even. There is only one kind of iteration if the root is odd and two kinds if the root…

General Mathematics · Mathematics 2022-10-28 Leonel Sternberg

We investigate the problems related to the Collatz map $T$ from the point of view of functional analysis. We associate with $T$ certain linear operator $\mathcal{T}$ and show that cycles and (hypothetical) diverging trajectory (generated by…

Functional Analysis · Mathematics 2022-06-02 Mikhail Neklyudov