On $k$-Shifted Antimagic Spider Forests

TL;DR

This paper proves that certain spider forests are $k$-shifted antimagic for all non-negative integers $k$, and identifies a range of $k$ values for which the graphs admit such labelings, extending antimagic graph theory.

Contribution

The paper establishes that specific spider forests are $k$-shifted antimagic for all $k eq -1$, and finds a positive integer $k_0$ such that the graphs are $k$-shifted antimagic for all $k$ in a symmetric range around zero.

Findings

Certain spider forests are $k$-shifted antimagic for all $k eq -1.

Existence of a positive integer $k_0 < m$ such that the graph is $k$-shifted antimagic for all $k$ in a symmetric range.

Extension of antimagic labeling results to $k$-shifted antimagic labelings for specific graph classes.

Abstract

Let $G(V,E)$ be a simple graph with $m$ edges. For a given integer $k$, a $k$-shifted antimagic labeling is a bijection $f: E(G) \to \{k+1, k+2, \ldots, k+m\}$ such that all vertices have different vertex-sums, where the vertex-sum of a vertex $v$ is the total of the labels assigned to the edges incident to $v$. A graph $G$ is {\it $k$-shifted antimagic} if it admits a $k$-shifted antimagic labeling. For the special case when $k=0$, a $0$-shifted antimagic labeling is known as {\it antimagic labeling}; and $G$ is {\it antimagic} if it admits an antimagic labeling. A spider is a tree with exactly one vertex of degree greater than two. A spider forest is a graph where each component is a spider. In this article, we prove that certain spider forests are $k$-shifted antimagic for all $k \geq 0$. In addition, we show that for a spider forest $G$ with $m$ edges, there exists a positive integer $k_0< m$ such that $G$ is $k$-shifted antimagic for all $k \geq k_0$ and $k \leq -(m+k_0+1)$.