Enumerative combinatorics
Some remarks on Catalan families
European Journal of Combinatorics
Short factorizations of permutations into transpositions
Discrete Mathematics
Chords, trees, and permutations
Discrete Mathematics
An introduction to the analysis of algorithms
An introduction to the analysis of algorithms
Percolation models and animals
European Journal of Combinatorics
Combinatorics of diagonally convex directed polyominoes
Proceedings of the 6th conference on Formal power series and algebraic combinatorics
Enumeration of noncrossing trees on a circle
Proceedings of the 7th conference on Formal power series and algebraic combinatorics
Regular Article: Enumeration of Symmetry Classes of Convex Polyominoes in the Square Lattice
Advances in Applied Mathematics
Analytic combinatorics of non-crossing configurations
Discrete Mathematics - Special issue on selected papers in honor of Henry W. Gould
The On-Line Encyclopedia of Integer Sequences
Calculemus '07 / MKM '07 Proceedings of the 14th symposium on Towards Mechanized Mathematical Assistants: 6th International Conference
Dyck paths with coloured ascents
European Journal of Combinatorics
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We present a simple bijection between diagonally convex directed (DCD) polyominoes with n diagonals and plane trees with 2n edges in which every vertex has even degree (even trees), which specializes to a bijection between parallelogram polyominoes and full binary trees. Next we consider a natural definition of symmetry for DCD-polyominoes, even trees, ternary trees, and non-crossing trees, and show that the number of symmetric objects of a given size is the same in all four cases.