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    Edge-magic labelings for constellations and armies of caterpillars

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    Let G=(V,E)G=(V,E) be an nn-vertex graph with mm edges. A function f:V∪E→{1,…,n+m}f : V \cup E \rightarrow \{1, \ldots, n+m\} is an edge-magic labeling of GG if ff is bijective and, for some integer kk, we have f(u)+f(v)+f(uv)=kf(u)+f(v)+f(uv) = k for every edge uv∈Euv \in E. Furthermore, if f(V)={1,…,n}f(V) = \{1, \ldots, n\}, then we say that ff is a super edge-magic labeling. A constellation, which is a collection of stars, is symmetric if the number of stars of each size is even except for at most one size. We prove that every symmetric constellation with an odd number of stars admits a super edge-magic labeling. We say that a caterpillar is of type (r,s)(r,s) if rr and ss are the sizes of its parts, where r≤sr \leq s. We also prove that every collection with an odd number of same-type caterpillars admits an edge-magic labeling
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