ORIGINAL_ARTICLE
ASSOCIATED (SEMI)HYPERGROUPS FROM DUPLEXES
In this paper using strongly duplexes we introduce a new class of (semi)hypergroups. The associated (semi)hypergroup from a strongly duplex is called duplex (semi)hypergroup. Two computer programs written in MATLAB show that the two groups $Z_{2n}$ and $Z_{n}times Z_{2}$ produce a strongly duplex and its associated hypergroup is a complementary feasible hypergroup.
http://jas.shahroodut.ac.ir/article_358_f99c12fe0b879e885797880dc7afd9b4.pdf
2015-02-01T11:23:20
2019-05-22T11:23:20
83
96
10.22044/jas.2015.358
Duplexes
semihypergroups
complementary feasible (semi)hypergroups
M.
Jafarpour
rmo4909@yahoo.com
true
1
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
LEAD_AUTHOR
F.
Alizadeh
falizadeh@yahoo.com
true
2
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
Department of Mathematics, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran.
AUTHOR
ORIGINAL_ARTICLE
ON THE EDGE COVER POLYNOMIAL OF CERTAIN GRAPHS
Let $G$ be a simple graph of order $n$ and size $m$. The edge covering of $G$ is a set of edges such that every vertex of $G$ is incident to at least one edge of the set. The edge cover polynomial of $G$ is the polynomial$E(G,x)=sum_{i=rho(G)}^{m} e(G,i) x^{i}$, where $e(G,i)$ is the number of edge coverings of $G$ of size $i$, and$rho(G)$ is the edge covering number of $G$. In this paper we study the edge cover polynomials of cubic graphs of order $10$. We show that all cubic graphs of order $10$ (especially the Petersen graph) are determined uniquely by their edge cover polynomials.
http://jas.shahroodut.ac.ir/article_359_03bd853b0f975a60d986af404d928abd.pdf
2015-02-01T11:23:20
2019-05-22T11:23:20
97
108
10.22044/jas.2015.359
Edge cover polynomial
edge covering
equivalence class
cubic graph
corona
S.
Alikhani
alikhani@yazd.ac.ir
true
1
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran.
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran.
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran.
LEAD_AUTHOR
S.
Jahari
s.jahari@gmail.com
true
2
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran.
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran.
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran.
AUTHOR
ORIGINAL_ARTICLE
ON ANNIHILATOR PROPERTIES OF INVERSE SKEW POWER SERIES RINGS
Let $alpha$ be an automorphism of a ring $R$. The authors [On skew inverse Laurent-serieswise Armendariz rings, Comm. Algebra 40(1) (2012) 138-156] applied the concept of Armendariz rings to inverse skew Laurent series rings and introduced skew inverse Laurent-serieswise Armendariz rings. In this article, we study on aspecial type of these rings and introduce strongly Armendariz rings of inverse skew power series type. We determine the radicals of the inverse skew Laurent series ring $R((x^{-1};alpha))$, in terms of those of $R$. We also prove that several properties transfer between $R$ and the inverse skew Laurent series extension $R((x^{-1};alpha))$, in case $R$ is a strongly Armendariz ring of inverse skew power series type.
http://jas.shahroodut.ac.ir/article_360_3c473d1d286abc25947c292a6b305359.pdf
2015-02-01T11:23:20
2019-05-22T11:23:20
109
124
10.22044/jas.2015.360
Inverse skew power series extensions
Radical property
Semicommutative rings
M.
Habibi
habibi.mohammad2@gmail.com
true
1
Department of Mathematics, University of Tafresh, P.O.Box 39518-79611, Tafresh, Iran.
Department of Mathematics, University of Tafresh, P.O.Box 39518-79611, Tafresh, Iran.
Department of Mathematics, University of Tafresh, P.O.Box 39518-79611, Tafresh, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
COHEN-MACAULAY HOMOLOGICAL DIMENSIONS WITH RESPECT TO AMALGAMATED DUPLICATION
In this paper we use "ring changed'' Gorenstein homological dimensions to define Cohen-Macaulay injective, projective and flat dimensions. For doing this we use the amalgamated duplication of the base ring with semi-dualizing ideals. Among other results, we prove that finiteness of these new dimensions characterizes Cohen-Macaulay rings with dualizing ideals.
http://jas.shahroodut.ac.ir/article_361_50a50dd113314eebf1bad604ed0e91b0.pdf
2015-02-01T11:23:20
2019-05-22T11:23:20
125
135
10.22044/jas.2015.361
Semi-dualizing ideal
Amalgamated duplication
Gorenstein homological dimension
Cohen-Macaulay homological dimension
A.
Esmaeelnezhad
esmaeilnejad@gmail.com
true
1
Faculty of Mathematical sciences and computer, University of Kharazmi, Tehran, Iran.
Faculty of Mathematical sciences and computer, University of Kharazmi, Tehran, Iran.
Faculty of Mathematical sciences and computer, University of Kharazmi, Tehran, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
COGENERATOR AND SUBDIRECTLY IRREDUCIBLE IN THE CATEGORY OF S-POSETS
In this paper we study the notions of cogenerator and subdirectly irreducible in the category of S-poset. First we give somenecessary and sufficient conditions for a cogenerator $S$-posets. Then we see that under some conditions, regular injectivity implies generator and cogenerator. Recalling Birkhoff's Representation Theorem for algebra, we study subdirectly irreducible S-posets and give this theorem for the category of ordered right acts over an ordered monoid. Among other things, we give the relations between cogenerators and subdirectly irreducible S-posets.
http://jas.shahroodut.ac.ir/article_371_cf285a5a87885ed211e1f128762fbc2f.pdf
2015-02-01T11:23:20
2019-05-22T11:23:20
137
146
10.22044/jas.2015.371
S-poset
cogenerator
regular injective
subdirectly irreducible
Gh.
Moghaddasi
r.moghadasi@hsu.ac.ir
true
1
Department of Mathematics, Hakikm Sabzevari University, P.O.Bo 397, Sabzevar,
Iran.
Department of Mathematics, Hakikm Sabzevari University, P.O.Bo 397, Sabzevar,
Iran.
Department of Mathematics, Hakikm Sabzevari University, P.O.Bo 397, Sabzevar,
Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
ON THE GROUPS WITH THE PARTICULAR NON-COMMUTING GRAPHS
Let $G$ be a non-abelian finite group. In this paper, we prove that $Gamma(G)$ is $K_4$-free if and only if $G cong A times P$, where $A$ is an abelian group, $P$ is a $2$-group and $G/Z(G) cong mathbb{ Z}_2 times mathbb{Z}_2$. Also, we show that $Gamma(G)$ is $K_{1,3}$-free if and only if $G cong {mathbb{S}}_3,~D_8$ or $Q_8$.
http://jas.shahroodut.ac.ir/article_372_7f1845805d519f0e1594759c85b7ed9d.pdf
2015-02-01T11:23:20
2019-05-22T11:23:20
147
151
10.22044/jas.2015.372
non-commuting graph
$K_4$-free graph
$K_{1
3}$-free graph
N.
Ahanjideh
ahanjidn@gmail.com
true
1
Department of pure Mathematics, Shahrekord University, P.O.Box 115, Shahrekord,
Iran.
Department of pure Mathematics, Shahrekord University, P.O.Box 115, Shahrekord,
Iran.
Department of pure Mathematics, Shahrekord University, P.O.Box 115, Shahrekord,
Iran.
LEAD_AUTHOR
H.
Mousavi
h.sadat68@yahoo.com
true
2
Department of pure Mathematics, Shahrekord University, P.O.Box 115, Shahrekord,
Iran.
Department of pure Mathematics, Shahrekord University, P.O.Box 115, Shahrekord,
Iran.
Department of pure Mathematics, Shahrekord University, P.O.Box 115, Shahrekord,
Iran.
AUTHOR