1 citations · 2 across the 3 of their papers we have counts for
10 papers
On divisibility of Narayana numbers by primes
Miklos Bona, Bruce Sagan
Using Kummer's Theorem, we give a necessary and sufficient condition for a Narayana number to be divisible by a given prime. We use this to derive certain properties of the Narayan…
The limit of a Stanley-Wilf sequence is not always rational, and layered patterns beat monotone patterns
Miklos Bona
We show the first known example for a pattern for which is not an integer. We find the exact value of the limit and show that it is irrati…
Two injective proofs of a conjecture of Simion
Miklós Bóna, Bruce E. Sagan
Simion conjectured the unimodality of a sequence counting lattice paths in a grid with a Ferrers diagram removed from the northwest corner. Recently, Hildebrand and then Wang prove…
Pattern frequency sequences and internal zeros
Miklos Bona, Bruce Sagan, Vincent Vatter
Consider the number of permutations in the symmetric group on n letters that contain c copies of a given pattern. As c varies (with n held fixed) these numbers form a sequence whos…
A self-dual poset on objects counted by the Catalan numbers and a type-B analogue
Miklós Bóna, Rodica Simion
We introduce two partially ordered sets, and , of the same cardinalities as the type-A and type-B noncrossing partition lattices. The ground sets of and $P^B…
A combinatorial proof of the log-concavity of the numbers of permutations with runs
Miklós Bóna, Richard Ehrenborg
We combinatorially prove that the number of permutations of length having runs is a log-concave sequence in , for all . We also give a new combinatorial proo…