An object grammar for the class of L-convex polyominoes
نویسندگان
چکیده
We consider the class of L-convex polyominoes, i.e. convex polyominoes where any two chosen cells can be connected simply using an internal path having at most one change of direction. The main result of the paper is the definition of an object grammar decomposition of this class, which gives combinatorial evidence of the rationality of the generating function, and suggests some new combinatorial properties. Mathematics Subject Classifications (2000). Primary 05A15; Secondary 05A17
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تاریخ انتشار 2006