Title
Zero-Sum Copies of Spanning Forests in Zero-Sum Complete Graphs
Abstract
For a complete graph $$K_n$$ of order n, an edge-labeling $$c:E(K_n)\rightarrow \{ -1,1\}$$ satisfying $$c(E(K_n))=0$$ , and a spanning forest F of $$K_n$$ , we consider the problem to minimize $$|c(E(F'))|$$ over all isomorphic copies $$F'$$ of F in $$K_n$$ . In particular, we ask under which additional conditions there is a zero-sum copy, that is, a copy $$F'$$ of F with $$c(E(F'))=0$$ . We show that there is always a copy $$F'$$ of F with $$|c(E(F'))|\le \Delta (F)+1$$ , where $$\Delta (F)$$ is the maximum degree of F. We conjecture that this bound can be improved to $$|c(E(F'))|\le (\Delta (F)-1)/2$$ and verify this for F being the star $$K_{1,n-1}$$ . Under some simple necessary divisibility conditions, we show the existence of a zero-sum $$P_3$$ -factor, and, for sufficiently large n, also of a zero-sum $$P_4$$ -factor.
Year
DOI
Venue
2022
10.1007/s00373-022-02539-2
Graphs and Combinatorics
Keywords
DocType
Volume
Zero-sum subgraph, Zero-sum Ramsey theory
Journal
38
Issue
ISSN
Citations 
5
0911-0119
0
PageRank 
References 
Authors
0.34
4
3
Name
Order
Citations
PageRank
Elena Mohr100.34
Johannes Pardey200.34
Dieter Rautenbach3946138.87