Abstract. Zeilberger's enumeration schemes can be used to completely automate the enumeration of many permutation classes. We extend his enumeration schemes so that they apply...
The only known enumeration of Buekenhout unitals occurs in the Desarguesian plane PG(2, q2). In this paper we develop general techniques for enumerating the nonsingular Buekenhout...
We consider Kasteleyn and Kasteleyn-Percus matrices, which arise in enumerating matchings of planar graphs, up to matrix operations on their rows and columns. If such a matrix is ...
Until now, the enumeration of connected graphs has been dealt with by probabilistic methods, by special combinatorial decompositions or by somewhat indirect formal series manipula...
In a recent work, M. Covington discusses the enumeration of two different sets of alignments of two strings of symbols using elementary combinatorial techniques. He defines two fu...
Various enumeration problems for classes of simply generated families of trees have been the object of investigation in the past. We mention the enumeration of independent subsets,...
We investigate and extend the notion of a good approximation with respect to the enumeration (De) and singleton (Ds) degrees. We refine two results by Griffith, on the inversion of...