Random Generation of Unlabelled Combinatorial Structures
نویسندگان
چکیده
A systematic method for generating unlabelled combinatorial structures uniformly at random is presented. It applies to structures that are decomposable, i.e., formally speciiable by grammars involving unions, products, sequences, multisets and cycles. All such structures of size n can be generated uniformly by either sequential algorithms of worst-case arithmetic complexity O(n 2) or by \boustrophedonic" algorithms of worst-case complexity O(n log n). The random generation procedures are derived automatically from a high level description of the combinatorial structures. An implementation of this system in the computer algebra system Maple is brieey described.
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