A bijective proof on circular compositions
نویسندگان
چکیده
The study of the preimage problem of an endofunction on circular compositions is motivated by the study of coloring circular-arc graphs. In this paper we establish a 1-1 correspondence between preimages of a given circular composition S and proper S-sequences, and also provide a necessary and suucient condition for a sequence of subsets of the natural numbers to be a proper S-sequence for some circular composition S.
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تاریخ انتشار 1995