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JOURNALS // Izvestiya of Saratov University. Mathematics. Mechanics. Informatics // Archive

Izv. Saratov Univ. Math. Mech. Inform., 2011 Volume 11, Issue 3(2), Pages 111–117 (Mi isu258)

This article is cited in 3 papers

Computer science

On lower bound of edge number of minimal edge 1-extension of starlike tree

M. B. Abrosimov

Saratov State University, Chair of Theoretical Foundations of Computer Security and Cryptography

Abstract: For a given graph $G$ with $n$ nodes, we say that graph $G^*$ is its 1-edge extension if for each edge $e$ of $G^*$ the subgraph $G^*-e$ contains graph $G$ up to isomorphism. Graph $G^*$ is minimal 1-edge extension of graph $G$ if $G^*$ has $n$ nodes and there is no 1-edge extension with $n$ nodes of graph $G$ having fewer edges than $G$. A tree is called starlike if it has exactly one node of degree greater than two. We give a lower bound of edge number of minimal edge 1-extension of starlike tree and provide family on which this bound is achieved.

Key words: minimal edge extension, starlike tree, fault tolerance.

UDC: 519.17

DOI: 10.18500/1816-9791-2011-11-3-2-111-117



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