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Related papers: Aliquot sequences with small starting values

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Define a(k,q) to be the smallest positive multiple of k such that the sum of its digits in base q is equal to k. The asymptotic behavior, lower and upper bound estimates of a(k,q) are investigated. A characterization of the minimality…

Number Theory · Mathematics 2015-05-13 H. Fredricksen , E. J. Ionascu , F. Luca , P. Stanica

A permutation is defined to be cycle-up-down if it is a product of cycles that, when written starting with their smallest element, have an up-down pattern. We prove bijectively and analytically that these permutations are enumerated by the…

Combinatorics · Mathematics 2009-09-30 Emeric Deutsch , Sergi Elizalde

This study involves definitions for multiple-counting regular and summation sequences of rho. My paper introduces and proves recurrent relationships for multiple-counting sequences and shows their association with Fermat's little theorem. I…

Number Theory · Mathematics 2019-01-07 Muhammed Hüsrev Cilasun

In this note we describe a method for finding prime numbers as fixed points of particularly simple sequences. Some basic calculations show that success rates for identifying primes this way are over 99.9%. In particular, it seems that the…

Number Theory · Mathematics 2019-07-24 Enrique Navarrete , Daniel Orellana

In this short note, we show a simple characterization of integers that reach records for a sequence described by adding binary strings to runs of 1's and 0's in a binary representation. In particular, we show that this set does not depend…

Number Theory · Mathematics 2018-10-08 Chai Wah Wu

An Inventory Sequence $(S_0, S_1, S_2, ...)$ is the iteration of the map $f$ defined roughly by taking an integer to its numericized description (e.g. $f(1381)=211318$ since "$1381$" has two $1$'s, one $3$, and one $8$). Our work analyzes…

Number Theory · Mathematics 2020-04-02 Onno M. Cain , Sela T. Enin

The minimal excludant statistic, which denotes the smallest positive integer that is not a part of an integer partition, has received great interest in recent years. In this paper, we move on to the smallest positive integer whose frequency…

Number Theory · Mathematics 2025-07-22 Shane Chern , Ernest X. W. Xia

It's the age-old recurrence with a twist: sum the last two terms and if the result is composite, divide by its smallest prime divisor to get the next term (e.g., 0, 1, 1, 2, 3, 5, 4, 3, 7, ...). These sequences exhibit pseudo-random…

Number Theory · Mathematics 2016-01-06 Richard K. Guy , Tanya Khovanova , Julian Salazar

In this article, we introduce the notion of almost consecutive partitions. A partition is almost consecutive if every term is consecutive, with the possible exception of the smallest one. We find formulas relating to the smallest parts of…

Combinatorics · Mathematics 2024-03-26 Rajat Gupta , Noah Lebowitz-Lockard

A subset of an abelian group is {\em sequenceable} if there is an ordering $(x_1, \ldots, x_k)$ of its elements such that the partial sums $(y_0, y_1, \ldots, y_k)$, given by $y_0 = 0$ and $y_i = \sum_{j=1}^i x_i$ for $1 \leq i \leq k$, are…

Combinatorics · Mathematics 2022-04-04 Simone Costa , Stefano Della Fiore , M. A. Ollis , Sarah Z. Rovner-Frydman

The Ulam sequence is given by $a_1 =1, a_2 = 2$, and then, for $n \geq 3$, the element $a_n$ is defined as the smallest integer that can be written as the sum of two distinct earlier elements in a unique way. This gives the sequence $1, 2,…

Combinatorics · Mathematics 2018-08-28 Noah Kravitz , Stefan Steinerberger

The comma sequence (1, 12, 35, 94, ...) is the lexicographically earliest sequence such that the difference of consecutive terms equals the concatenation of the digits on either side of the comma separating them. The behavior of a…

Number Theory · Mathematics 2024-09-27 Robert Dougherty-Bliss , Natalya Ter-Saakov

We investigate a descent on simple graphs, starting with the complete graph on $n$ vertices and ending up with the cycle graph by removing one edge after another. We obtain quantitative results showing that graphs with large diameter must…

Combinatorics · Mathematics 2018-02-28 Katja Mönius , Jörn Steuding , Pascal Stumpf

Sequential analysis encompasses simulation theories and methods where the sample size is determined dynamically based on accumulating data. Since the conceptual inception, numerous sequential stopping rules have been introduced, and many…

Methodology · Statistics 2026-04-02 Jiezhong Wu , Reiichiro Kawai

A set is introreducible if it can be computed by every infinite subset of itself. Such a set can be thought of as coding information very robustly. We investigate introreducible sets and related notions. Our two main results are that the…

Logic · Mathematics 2020-11-09 Noam Greenberg , Matthew Harrison-Trainor , Ludovic Patey , Dan Turetsky

Infinite sequences are of tremendous theoretical and practical importance, and in the Information Age sequences of 0s and 1s are of particular interest. Over the past century, the field of symbolic dynamics has developed to study sequences…

Dynamical Systems · Mathematics 2025-04-02 Natalie Priebe Frank , May Mei , Kitty Yang

We present a variety of numerical data related to the growth of terms in aliquot sequences, iterations of the function $s(n) = \sigma(n) - n$. First, we compute the geometric mean of the ratio $s_k(n)/s_{k-1}(n)$ of $k$th iterates for $n…

Number Theory · Mathematics 2021-10-28 Kevin Chum , Richard K. Guy , Michael J. Jacobson, , Anton S. Mosunov

This work uses a simple quantum computer model to discuss the randomness of bit strings originated from integer sequences. The considered quantum computer model has three elements: a processing unit responsible for a mathematical operation,…

Quantum Physics · Physics 2015-05-05 R. V. Ramos

Characterizations of finite sequences $\beta_{1}<\cdots<\beta_{n}$ representing expected values of order statistics from a random sample of size $n$ are given. As a by-product, a characterization of binomial mixtures, when the mixing random…

Probability · Mathematics 2022-05-02 A. Okolewski , N. Papadatos

Based on Euclid's algorithm, we find a kind of special sequences which play an interesting role in the study of primes. We call them W Sequences. They not only ties up the distribution of primes in short interval but also enables us to give…

General Mathematics · Mathematics 2009-09-15 Shaohua Zhang