×

Clean graph of a ring. (English) Zbl 1477.13005

Let \(R\) be a ring (not necessarily commutative) with identity. The clean graph \(Cl(R)\) of a ring \(R\) is a graph with vertices in form \((e, u)\), where \(e\) is an idempotent and \(u\) is a unit of \(R\); and two distinct vertices \((e, u)\) and \((f, v)\) are adjacent if and only if \(ef = fe = 0\) or \(uv = vu = 1\). This paper introduced and studied some basic properties of the clean graph \(Cl(R)\) and its subgraphs \(Cl_{1}(R)\) and \(Cl_{2}(R)\). In Section 2, the authors investigated the graph properties of \(Cl_{2}(R)\) such as diameter, maximum and minimum degree, regularity, etc. Among many results, they gave a necessary and sufficient condition for the connectedness of \(Cl_{2}(R)\), that is, \(Cl_{2}(R)\) is connected if and only if \(R\) has a nontrivial idempotent. Moreover, if \(Cl_{2}(R)\) is connected, then diam\((Cl_{2}(R))\leq 3\). Also, they proved that \(Cl_{2}(R)\) is regular if and only if \(|U(R)| = 1\) or \(R\) has no nontrivial idempotent and \(U''(R) =\emptyset\). In Section 3, They showed that the parameters of clean graph of every commutative Artinian ring depend to the number of maximal ideals of it. It is proved that the clique number \(\omega(Cl_{2}(R)) = \chi(Cl_{2}(R))\), for every commutative Artinian ring \(R\). Moreover, the exact value of \(\omega(Cl_{2}(R))\) is given. Among other results, the independence number and domination number of \(Cl_{2}(R)\) are given.

MSC:

13A15 Ideals and multiplicative ideal theory in commutative rings
05C25 Graphs and abstract algebra (groups, rings, fields, etc.)
13A70 General commutative ring theory and combinatorics (zero-divisor graphs, annihilating-ideal graphs, etc.)
Full Text: DOI

References:

[1] Abdioğlu, C., Zero-divisor graph of matrix rings and Hurwitz rings, Turk. J. Math.40(1) (2016) 201-209. · Zbl 1424.16057
[2] Abdioğlu, C., Çelikel, E. Yetkin and Das, A., The Armendariz graph of a ring, Discuss. Math. Gen. Algebra Appl.38(2) (2018) 189-196. · Zbl 1463.05238
[3] Akbari, S., Habibi, M., Majidinya, A. and Manaviyat, R., The inclusion ideal graph of rings, Commun. Algebra43(6) (2015) 2457-2465. · Zbl 1315.05072
[4] Akbari, S., Habibi, M., Majidinya, A. and Manaviyat, R., On the idempotent graph of a ring, J. Algebra Appl.12(6) (2013). · Zbl 1266.05051
[5] Anderson, D. D. and Camillo, V. P., Commutative rings whose elements are a sum of a unit and idempotent, Commun. Algebra30(7) (2002) 3327-3336. · Zbl 1083.13501
[6] Anderson, D. F. and Livingston, P. S., The zero-divisor graph of a commutative ring, J. Algebra217 (1999) 434-447. · Zbl 0941.05062
[7] Atiyah, M. F. and Macdonald, I. G., Introduction to Commutative Algebra (Anderson-Wesley Publishing Company, 1969). · Zbl 0175.03601
[8] Aykac, S., Akgunes, N. and Cevik, A. S., Analysis of Zagreb indices over zero-divisor graphs of commutative rings, Asian-European J. Math.12(6) (2019) 2040003-1-19. · Zbl 1423.13140
[9] Beck, I., Coloring of commutative rings, J. Algebra116(1) (1988) 208-226. · Zbl 0654.13001
[10] Han, J. and Nicholson, W. K., Extensions of clean rings, Commun. Algebra29(6) (2001) 2589-2595. · Zbl 0989.16015
[11] Lam, T. Y., A First Course in Noncommutative Rings (Springer-Verlag, New York, 2001). · Zbl 0980.16001
[12] Nicholson, W. K., Lifting idempotents and exchange rings, Trans. Amer. Math. Soc.229 (1977) 269-278. · Zbl 0352.16006
[13] Nicholson, W. K. and Varadarajan, K., Countable linear transformations are clean, Proc. Amer. Math. Soc.126 (1998) 61-64. · Zbl 0905.16009
[14] Nicholson, W. K., Varadarajan, K. and Zhou, Y., Clean endomorphism rings, Arch. Math.83 (2004) 340-343. · Zbl 1067.16051
[15] Nicholson, W. K. and Zhou, Y., Rings in which elements are uniquely the sum of an idempotent and a unit, Glasgow Math. J.46(2) (2004) 227-236. · Zbl 1057.16007
[16] West, D. B., Introduction to Graph Theory (Prentice Hall, Upper Saddle River, 2001).
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.