Zobrazeno 1 - 10
of 38
pro vyhledávání: '"Viorel Nitica"'
Autor:
Viorel Nitica, Andrew Torok
Publikováno v:
Symmetry, Vol 12, Iss 9, p 1392 (2020)
We consider the following semigroup problem: is the closure of a semigroup S in a topological vector space X a group when S does not lie on “one side” of any closed hyperplane of X? Whereas for finite dimensional spaces, the answer is positive, w
Externí odkaz:
https://doaj.org/article/edbb741812ca433992178c0a19c5577e
Autor:
Viorel Nitica, Andrei Török
Publikováno v:
Axioms, Vol 4, Iss 1, Pp 84-101 (2015)
Currently, there is great renewed interest in proving the topological transitivity of various classes of continuous dynamical systems. Even though this is one of the most basic dynamical properties that can be investigated, the tools used by various
Externí odkaz:
https://doaj.org/article/23f16f0d405d40fbb1035a0af34ca8af
Autor:
Anatole Katok, Viorel Niţică
This self-contained monograph presents rigidity theory for a large class of dynamical systems, differentiable higher rank hyperbolic and partially hyperbolic actions. This first volume describes the subject in detail and develops the principal method
Autor:
Cem Ekinci, Viorel Nitica
Publikováno v:
Open Journal of Discrete Mathematics. 10:69-73
Motivated by their intrinsic interest and by applications to the study of numeric palindromes and other sequences of integers, we discover a method for producing infinite sets of solutions and almost solutions of the equation N⋅M = reversal (N⋅M)
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::6a6bcb1863f60090279b3262b89738c6
https://doi.org/10.4236/ojdm.2020.103007
https://doi.org/10.4236/ojdm.2020.103007
Autor:
Catalin Nitica, Viorel Nitica
Publikováno v:
Open Journal of Discrete Mathematics. 10:1-3
Let b ≥ 2 be a numeration base. A b-weak additive Ramanujan-Hardy (or b-wARH) number N is a non-negative integer for which there exists at least one non-negative integer A, such that the sum of A and the sum of base b digits of N, added to the reve
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::691935d1d928f65b512311896a4a9879
https://doi.org/10.4236/ojdm.2020.101001
https://doi.org/10.4236/ojdm.2020.101001
Autor:
Catalin Nitica, Viorel Nitica
Publikováno v:
Open Journal of Discrete Mathematics. :1-6
In this note, for any pair of natural numbers (n,k), n≥3, k≥1, and 2k
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::46ef784f7e7f4c06f1360fddecc2f1ee
https://doi.org/10.4236/ojdm.2019.91001
https://doi.org/10.4236/ojdm.2019.91001
Autor:
Viorel Nitica, Andrei Török
Publikováno v:
Discrete & Continuous Dynamical Systems - S. 12:2365-2377
If \begin{document}$ S $\end{document} is a semigroup in \begin{document}$ \mathbb{R}^n $\end{document} that is not separated by a linear functional, then it is known that the closure of \begin{document}$ S $\end{document} is a group. We investigate
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ff94dcb1fa5c8548d28ac0aa36621dd2
https://doi.org/10.3934/dcdss.2019148
https://doi.org/10.3934/dcdss.2019148
Autor:
Viorel Nitica
Publikováno v:
Open Journal of Discrete Mathematics. :48-63
In a recent paper, we revisited Golomb’s hierarchy for tiling capabilities of finite sets of polyominoes. We considered the case when only translations are allowed for the tiles. In this classification, for several levels in Golomb’s hierarchy, m
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::94b4b196e97989d100b234646bdf1511
https://doi.org/10.4236/ojdm.2018.82005
https://doi.org/10.4236/ojdm.2018.82005
Autor:
Viorel Nitica
Publikováno v:
Open Journal of Discrete Mathematics. :165-176
We consider tilings of deficient rectangles by the set T4 of ribbon L-tetro-minoes. A tiling exists if and only if the rectangle is a square of odd side. The missing cell has to be on the main NW-SE diagonal, in an odd position if the square is (4m+1
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::3cfd198a56d63e84de122d8c54bac04a
https://doi.org/10.4236/ojdm.2017.73015
https://doi.org/10.4236/ojdm.2017.73015
Autor:
Viorel Nitica, Premalatha Junius
Publikováno v:
Open Journal of Discrete Mathematics. :87-102
We show that the least number of cells (the gap number) one needs to take out from a rectangle with integer sides of length at least 2 in order to be tiled by ribbon right trominoes is less than or equal to 4. If the sides of the rectangle are of len
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d9c4127cf72c2691d3e75fe4e5c0794a
https://doi.org/10.4236/ojdm.2017.72010
https://doi.org/10.4236/ojdm.2017.72010