<abstract xmlns="http://www.w3.org/1999/xhtml">

Bishop Independence concerns determining the maximum number of bishops that can be placed on a board such that no bishop can attack any other bishop. This paper presents the solution to the bishop independence problem, determining the bishop independence number, for all sizes of boards on the surface of a square prism.
</abstract>

Bishop Independence on the Surface of a Square Prism

<abstract xmlns="http://www.w3.org/1999/xhtml">

We define the <italic>queens (resp., rooks) diameter-separation number</italic> to be the minimum number of pawns for which some placement of those pawns on an <italic>n</italic> × <italic>n</italic> board produces a board with a queens graph (resp., rooks graph) with a desired diameter <italic>d</italic>. We determine these numbers for some small values of <italic>d</italic>.
</abstract>

Diameter-Separation of Chessboard Graphs

<abstract xmlns="http://www.w3.org/1999/xhtml">

In this paper we consider a scenario where there are several algorithms for solving a given problem. Each algorithm is associated with a probability of success and a cost, and there is also a penalty for failing to solve the problem. The user may run one algorithm at a time for the specified cost, or give up and pay the penalty. The probability of success may be implied by randomization in the algorithm, or by assuming a probability distribution on the input space, which lead to different variants of the problem. The goal is to minimize the expected cost of the process under the assumption that the algorithms are independent. We study several variants of this problem, and present possible solution strategies and a hardness result.
</abstract>

Adjustable Coins

<abstract xmlns="http://www.w3.org/1999/xhtml">

We discuss a generalization of logic puzzles in which truth-tellers and liars are allowed to deviate from their pattern in case of one particular question: “Are you guilty?”
</abstract>

Who is Guilty?

AHEAD OF PRINT

Volume 11 (2024): Issue 18 (March 2024)

Volume 10 (2023): Issue 17 (January 2023)

Volume 9 (2022): Issue 16 (June 2022)

Volume 8 (2021): Issue 15 (November 2021)

Volume 8 (2021): Issue 14 (October 2021)

Volume 7 (2020): Issue 13 (November 2020)

Volume 6 (2019): Issue 12 (December 2019)

Volume 6 (2019): Issue 11 (September 2019)

Volume 5 (2018): Issue 10 (December 2018)

Volume 5 (2018): Issue 9 (September 2018)

Volume 4 (2017): Issue 8 (December 2017)

Volume 4 (2017): Issue 7 (May 2017)

Volume 3 (2016): Issue 6 (December 2016)

Volume 3 (2016): Issue 5 (March 2016)

Recreational Mathematics Magazine

The Recreational Mathematics Magazine is published by the Ludus Association with the support of the　Interuniversity Centre for the History of Science and Technology. The journal is electronic and semiannual, and focuses on results that provide amusing, witty but nonetheless original and scientifically profound mathematical nuggets. The issues are published in the exact moments of the equinox. It's a magazine for mathematicians, and other mathematics lovers, who enjoy imaginative ideas, non-standard approaches, and surprising procedures. Occasionally, some papers that do not require any mathematical background will be published.  Examples of topics to be adressed include: games and puzzles, problems, mathmagic, mathematics and arts, math and fun with algorithms, reviews and news.  Recreational mathematics focuses on insight, imagination and beauty. Historically, we know that some areas of mathematics are strongly linked to recreational mathematics - probability, graph theory, number theory, etc. Thus, recreational mathematics can also be very serious. Many professional mathematicians confessed that their love for math was gained when reading the articles by Martin Gardner in Scientific American.  While there are conferences related to the subject as the amazing Gathering for Gardner, and high-quality magazines that accept recreational papers as the American Mathematical Monthly, the number of initiatives related to this important subject is not large.  This context led us to launch this magazine. We will seek to provide a quality publication. We shall endeavor to be read with pleasure. In mathematics, the most important are the underlying ideas and nothing is as exciting as an amazing idea. So, we seek sophistication, imagination and awe.  Rejection Rate   50%   Recreational Mathematics Magazine is a journal for mathematicians who enjoy imaginative ideas, non-standard approaches, and surprising procedures. The journal addresses such topics as: games and puzzles, problems, mathmagic, mathematics and arts, math and fun with algorithms.  Archiving  Sciendo archives the contents of this journal in Portico - digital long-term preservation service of scholarly books, journals and collections.  Plagiarism Policy  The editorial board is participating in a growing community of Similarity Check System's users in order to ensure that the content published is original and trustworthy. Similarity Check is a medium that allows for comprehensive manuscripts screening, aimed to eliminate plagiarism and provide a high standard and quality peer-review process.  Target group:   researchers in the fields of games and puzzles, problems, mathmagic, mathematics and arts, math and fun with algorithms  Financed by Fundação para a Ciência e a Tecnologia, I.P./MCTES through national funds (PIDDAC) – PTDC/HAR-HIS/28627/2017, UIDB/00286/2020 and UIDB/00678/2020. 