Zobrazeno 1 - 10
of 22
pro vyhledávání: '"Raianu, Şerban"'
We show that the four best-known substitutions used to integrate secant rely on different rational parametrizations of conic sections, coming from stereographic projections. We also investigate other possible explanations for the four substitutions,
Externí odkaz:
http://arxiv.org/abs/2204.11187
Autor:
Morton, Patrick, Raianu, Serban
It is shown that $c=-29/16$ is the unique rational number of smallest denominator, and the unique rational number of smallest numerator, for which the map $f_c(x) = x^2+c$ has a rational periodic point of period $3$. Several arithmetic conditions on
Externí odkaz:
http://arxiv.org/abs/2105.07435
Autor:
Morton, Patrick, Raianu, Serban
Publikováno v:
In Journal of Number Theory November 2022 240:685-729
We give a possible explanation for the mystery of a missing number in the statement of a problem that asks for the non-negative integers to be partitioned into three subsets. We interpret the missing number as one of the clues that can lead to a more
Externí odkaz:
http://arxiv.org/abs/1708.00858
Our main source of inspiration was a talk by Hendrik Lenstra on harmonic numbers, which are numbers whose only prime factors are two or three. Gersonides proved 675 years ago that one can be written as a difference of harmonic numbers in only four wa
Externí odkaz:
http://arxiv.org/abs/1708.00620
Autor:
Iovanov, Miodrag C., Raianu, Serban
We provide a very short approach to several fundamental results for Hopf algebras with nonzero integrals. Besides being short, our approach is the first to prove the bijectivity of the antipode without using the uniqueness of the integrals of Hopf al
Externí odkaz:
http://arxiv.org/abs/1001.0180
For $A$ a Hopf algebra of arbitrary dimension over a field $K$, it is well-known that if $A$ has nonzero integrals, or, in other words, if the coalgebra $A$ is co-Frobenius, then the space of integrals is one-dimensional and the antipode of $A$ is bi
Externí odkaz:
http://arxiv.org/abs/0805.2401
We compute liftings of the Nichols algebra of a Yetter-Drinfeld module of Cartan type $B_2$ subject to the small restriction that the diagonal elements of the braiding matrix are primitive $n$th roots of 1 with odd $n\neq 5$. As well, we compute the
Externí odkaz:
http://arxiv.org/abs/math/0204075
Autor:
Quinn, Declan, Raianu, Şerban
Publikováno v:
Proceedings of the American Mathematical Society, 2003 Jan 01. 131(1), 29-33.
Externí odkaz:
https://www.jstor.org/stable/1194220
Autor:
Raianu, Şerban
Publikováno v:
Bulletin mathématique de la Société des Sciences Mathématiques de Roumanie, 2013 Jan 01. 56(3)
Externí odkaz:
https://www.jstor.org/stable/43679353