The number of $k$-parallelogram polyominoes
A convex polyomino is $k$-$\textit{convex}$ if every pair of its cells can be connected by means of a $\textit{monotone path}$, internal to the polyomino, and having at most $k$ changes of direction. The number $k$-convex polyominoes of given semi-perimeter has been determined only for small values...
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Discrete Mathematics & Theoretical Computer Science
2013-01-01
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Series: | Discrete Mathematics & Theoretical Computer Science |
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Online Access: | https://dmtcs.episciences.org/2370/pdf |
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author | Daniela Battaglino Jean-Marc Fédou Simone Rinaldi Samanta Socci |
author_facet | Daniela Battaglino Jean-Marc Fédou Simone Rinaldi Samanta Socci |
author_sort | Daniela Battaglino |
collection | DOAJ |
description | A convex polyomino is $k$-$\textit{convex}$ if every pair of its cells can be connected by means of a $\textit{monotone path}$, internal to the polyomino, and having at most $k$ changes of direction. The number $k$-convex polyominoes of given semi-perimeter has been determined only for small values of $k$, precisely $k=1,2$. In this paper we consider the problem of enumerating a subclass of $k$-convex polyominoes, precisely the $k$-$\textit{convex parallelogram polyominoes}$ (briefly, $k$-$\textit{parallelogram polyominoes}$). For each $k \geq 1$, we give a recursive decomposition for the class of $k$-parallelogram polyominoes, and then use it to obtain the generating function of the class, which turns out to be a rational function. We are then able to express such a generating function in terms of the $\textit{Fibonacci polynomials}$. |
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issn | 1365-8050 |
language | English |
last_indexed | 2024-04-25T02:01:37Z |
publishDate | 2013-01-01 |
publisher | Discrete Mathematics & Theoretical Computer Science |
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series | Discrete Mathematics & Theoretical Computer Science |
spelling | doaj.art-3e0d86ce64574a599af73a52947906b62024-03-07T14:52:36ZengDiscrete Mathematics & Theoretical Computer ScienceDiscrete Mathematics & Theoretical Computer Science1365-80502013-01-01DMTCS Proceedings vol. AS,...Proceedings10.46298/dmtcs.23702370The number of $k$-parallelogram polyominoesDaniela Battaglino0Jean-Marc Fédou1Simone Rinaldi2https://orcid.org/0000-0003-3377-5331Samanta Socci3Laboratoire d'Informatique, Signaux, et Systèmes de Sophia-Antipolis (I3S) / Equipe MC3Laboratoire d'Informatique, Signaux, et Systèmes de Sophia-Antipolis (I3S) / Equipe MC3Dipartimento di Matematica e Informatica [Siena]Dipartimento di Matematica e Informatica [Siena]A convex polyomino is $k$-$\textit{convex}$ if every pair of its cells can be connected by means of a $\textit{monotone path}$, internal to the polyomino, and having at most $k$ changes of direction. The number $k$-convex polyominoes of given semi-perimeter has been determined only for small values of $k$, precisely $k=1,2$. In this paper we consider the problem of enumerating a subclass of $k$-convex polyominoes, precisely the $k$-$\textit{convex parallelogram polyominoes}$ (briefly, $k$-$\textit{parallelogram polyominoes}$). For each $k \geq 1$, we give a recursive decomposition for the class of $k$-parallelogram polyominoes, and then use it to obtain the generating function of the class, which turns out to be a rational function. We are then able to express such a generating function in terms of the $\textit{Fibonacci polynomials}$.https://dmtcs.episciences.org/2370/pdfconvex polyominoesl-convex polyominoesrational generating functionsfibonacci polynomials[info.info-dm] computer science [cs]/discrete mathematics [cs.dm] |
spellingShingle | Daniela Battaglino Jean-Marc Fédou Simone Rinaldi Samanta Socci The number of $k$-parallelogram polyominoes Discrete Mathematics & Theoretical Computer Science convex polyominoes l-convex polyominoes rational generating functions fibonacci polynomials [info.info-dm] computer science [cs]/discrete mathematics [cs.dm] |
title | The number of $k$-parallelogram polyominoes |
title_full | The number of $k$-parallelogram polyominoes |
title_fullStr | The number of $k$-parallelogram polyominoes |
title_full_unstemmed | The number of $k$-parallelogram polyominoes |
title_short | The number of $k$-parallelogram polyominoes |
title_sort | number of k parallelogram polyominoes |
topic | convex polyominoes l-convex polyominoes rational generating functions fibonacci polynomials [info.info-dm] computer science [cs]/discrete mathematics [cs.dm] |
url | https://dmtcs.episciences.org/2370/pdf |
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