Ordered trees an noncrossing partitions
Discrete Mathematics
Enumerative combinatorics
p,q-Stirling numbers and set partition statistics
Journal of Combinatorial Theory Series A
On the structure of the lattice of noncrossing partitions
Discrete Mathematics
Linear trees and RNA secondary structure
Discrete Applied Mathematics
On abab-free and abba-free set partitions
European Journal of Combinatorics
Discrete Mathematics
On trees and noncrossing partitions
Discrete Applied Mathematics
Combinatorics of RNA secondary structures
Discrete Applied Mathematics - Special volume on computational molecular biology DAM-CMB series volume 2
Discrete Mathematics
A bijection between ordered trees and 2-Motzkin paths and its many consequences
Discrete Mathematics
A Construction for Enumerating k-coloured Motzkin Paths
COCOON '95 Proceedings of the First Annual International Conference on Computing and Combinatorics
Extended set partitions with successions
European Journal of Combinatorics
Enumeration of gap-bounded set partitions
Journal of Automata, Languages and Combinatorics
Heisenberg characters, unitriangular groups, and Fibonacci numbers
Journal of Combinatorial Theory Series A
Partitions and partial matchings avoiding neighbor patterns
European Journal of Combinatorics
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In this paper, we present a reduction algorithm which transforms m-regular partitions of [n] = {1, 2 ..... n} to (m - 1)-regular partitions of [n - 1]. We show that this algorithm preserves the noncrossing property. This yields a simple explanation of an identity due to Simion-Ullman and Klazar in connection with enumeration problems on noncrossing partitions and RNA secondary structures. For ordinary noncrossing partitions, the reduction algorithm leads to a representation of noncrossing partitions in terms of independent arcs and loops, as well as an identity of Simion and Ullman which expresses the Narayana numbers in terms of the Catalan numbers.