Given a hypergraph and a function f : V () → , we say that is f-choosable if there is a proper vertex colouring ϕ of such that ϕ (v) ∈ L(v) for all v ∈ V (), where L : V () → 2 is any assignment of f(v) colours to a vertex v. The sum choice number isc() of is defined to be the minimum of Σv∈V()f(v) over all functions f such that is f-choosable. For an arbitrary hypergraph the inequality χsc() ≤ |V ()| + |ɛ ()| holds, and hypergraphs that attain this upper bound are called sc-greedy. In this paper we characterize sc-greedy hypergraphs that are unions of a hypercycle and a hyperpath having at most two vertices in common. Consequently, we characterize the hypergraphs of this type that are forbidden for the class of sc-greedy hypergraphs.
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