Zobrazeno 1 - 10
of 63
pro vyhledávání: '"Birmajer, Daniel"'
In this paper, we study pattern avoidance for stabilized-interval-free (SIF) permutations. These permutations are contained in the set of indecomposable permutations and in the set of derangements. We enumerate pattern-avoiding SIF permutations for c
Externí odkaz:
http://arxiv.org/abs/2306.03155
Publikováno v:
Discrete Mathematics & Theoretical Computer Science, vol. 24, no. 1, Combinatorics (March 21, 2022) dmtcs:8350
Motivated by the study of pattern avoidance in the context of permutations and ordered partitions, we consider the enumeration of weak-ordering chains obtained as leaves of certain restricted rooted trees. A tree of order $n$ is generated by insertin
Externí odkaz:
http://arxiv.org/abs/2108.04302
Publikováno v:
J. Integer Seq. 24 (2021), no. 1, Article 21.1.3
We present several bijections, in terms of combinatorial objects counted by the Schr\"oder numbers, that are then used (via coloring) for the construction and enumeration of rational Schr\"oder paths with integer slope, ordered rooted trees, and simp
Externí odkaz:
http://arxiv.org/abs/1908.08103
Publikováno v:
Advances in Applied Mathematics 99 (2018), 94-108
We study a class of rational Dyck paths with slope (2m+1)/2 corresponding to factor-free Dyck words, as introduced by P. Duchon. We show that, for the slopes considered in this paper, the language of factor-free Dyck words is generated by an auxiliar
Externí odkaz:
http://arxiv.org/abs/1804.11244
Publikováno v:
Discrete Math. 342 (2019), no. 1, 38-54
We introduce a family of sequence transformations, defined via partial Bell polynomials, that may be used for a systematic study of a wide variety of problems in enumerative combinatorics. This family includes some of the transformations listed in th
Externí odkaz:
http://arxiv.org/abs/1803.07727
Given two relatively prime positive integers $\alpha$ and $\beta$, we consider simple lattice paths (with unit East and unit North steps) from $(0,0)$ to $(\alpha k,\beta k)$, and enumerate them by their left and right bounces with respect to the lin
Externí odkaz:
http://arxiv.org/abs/1707.09918
Publikováno v:
Congr. Numer. 228 (2017), 245-251
For $a,b\in\mathbb{N}_0$, we consider $(an+b)$-color compositions of a positive integer $\nu$ for which each part of size $n$ admits $an+b$ colors. We study these compositions from the enumerative point of view and give a formula for the number of $(
Externí odkaz:
http://arxiv.org/abs/1707.07798
Publikováno v:
Discrete Applied Mathematics 244 (2018), 36-43
Motivated by independent results of Bizley and Duchon, we study rational Dyck paths and their subset of factor-free elements. On the one hand, we give a bijection between rational Dyck paths and regular Dyck paths with ascents colored by factor-free
Externí odkaz:
http://arxiv.org/abs/1606.02183
Publikováno v:
Lattice Path Combinatorics and Applications, G. E. Andrews, C. Krattenthaler, A. Krinik (Eds.), Springer, 2019, 155-165
We consider a class of lattice paths with certain restrictions on their ascents and down steps and use them as building blocks to construct various families of Dyck paths. We let every building block $P_j$ take on $c_j$ colors and count all of the re
Externí odkaz:
http://arxiv.org/abs/1602.03550
Publikováno v:
Journal of Combinatorics 9 (2018), no. 2, 221-232
For a given integer $d\ge 1$, we consider $\binom{n+d-1}{d}$-color compositions of a positive integer $\nu$ for which each part of size $n$ admits $\binom{n+d-1}{d}$ colors. We give explicit formulas for the enumeration of such compositions, generali
Externí odkaz:
http://arxiv.org/abs/1601.01595