## Missouri Journal of Mathematical Sciences

### New Forms of Contra-Continuity in Ideal Topology Spaces

#### Abstract

In this paper, we apply the notion of $e$-$\I$-open sets \cite{Wadei6} in ideal topological spaces to present and study new classes of functions called contra $e$-$\I$-continuous functions, almost-$e$-$\I$-continuous, almost contra-$e$-$\I$-continuous, and almost weakly-$e$-$\I$-continuous along with their several properties, characterizations and mutual relationships. Relationships between their new classes and other classes of functions are established and some characterizations of their new classes of functions are studied. Further, we introduce new types of graphs, called $e$-$\I$-closed, contra-$e$-$\I$-closed, and strongly contra-$e$-$\I$-closed graphs via $e$-$\I$-open sets. Several characterizations and properties of such notions are investigated.

#### Article information

Source
Missouri J. Math. Sci., Volume 26, Issue 1 (2014), 33-47.

Dates
First available in Project Euclid: 10 July 2014

https://projecteuclid.org/euclid.mjms/1404997107

Digital Object Identifier
doi:10.35834/mjms/1404997107

Mathematical Reviews number (MathSciNet)
MR3263540

Zentralblatt MATH identifier
1300.54005

#### Citation

Al-Omeri, Wadei; Noorani, Mohd. Salmi Md.; Al-Omari, A. New Forms of Contra-Continuity in Ideal Topology Spaces. Missouri J. Math. Sci. 26 (2014), no. 1, 33--47. doi:10.35834/mjms/1404997107. https://projecteuclid.org/euclid.mjms/1404997107

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