Results 51 to 60 of about 56,637 (162)

Permutations avoiding an increasing number of length-increasing forbidden subsequences [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2000
A permutation π is said to be τ -avoiding if it does not contain any subsequence having all the same pairwise comparisons as τ . This paper concerns the characterization and enumeration of permutations which avoid a set F^j of subsequences increasing ...
Elena Barcucci   +3 more
doaj   +1 more source

q-Catalan numbers

open access: yesJournal of Combinatorial Theory, Series A, 1985
Let \(C_ n\) be the set of Catalan words: binary words with n zeros and n ones such that each initial segment has at least as many zeros and ones. For \(w\in C_ n\), let d(w) be the number of descents, a(w) be the sum over all descents of the number of zeros to the left, b(w) be the sum over all descents of the number of ones to the left.
Fürlinger, J, Hofbauer, J
openaire   +1 more source

Catalan pairs and Fishburn triples

open access: yes, 2015
Disanto, Ferrari, Pinzani and Rinaldi have introduced the concept of 'Catalan pair', which is a pair of partial orders (S,R) satisfying certain axioms.
Jelínek, Vít
core   +1 more source

Growing and Destroying Catalan-Stanley Trees [PDF]

open access: yesDiscrete Mathematics & Theoretical Computer Science, 2018
Stanley lists the class of Dyck paths where all returns to the axis are of odd length as one of the many objects enumerated by (shifted) Catalan numbers.
Benjamin Hackl, Helmut Prodinger
doaj   +1 more source

A combinatorial identity with application to Catalan numbers

open access: yes, 2005
By a very simple argument, we prove that if $l,m,n$ are nonnegative integers then $$\sum_{k=0}^l(-1)^{m-k}\binom{l}{k}\binom{m-k}{n}\binom{2k}{k-2l+m} =\sum_{k=0}^l\binom{l}{k}\binom{2k}{n}\binom{n-l}{m+n-3k-l}.
Pan, Hao, Sun, Zhi-Wei
core   +6 more sources

Success Run Waiting Times and Fuss-Catalan Numbers

open access: yesJournal of Probability and Statistics, 2015
We present power series expressions for all the roots of the auxiliary equation of the recurrence relation for the distribution of the waiting time for the first run of k consecutive successes in a sequence of independent Bernoulli trials, that is, the ...
S. J. Dilworth, S. R. Mane
doaj   +1 more source

On generalized bihyperbolic Mersenne numbers [PDF]

open access: yesMathematica Bohemica
In this paper, a new generalization of Mersenne bihyperbolic numbers is introduced. Some of the properties of presented numbers are given. A general bilinear index-reduction formula for the generalized bihyperbolic Mersenne numbers is obtained.
Dorota Bród, Anetta Szynal-Liana
doaj   +1 more source

Some Identities on the Twisted q-Analogues of Catalan-Daehee Numbers and Polynomials

open access: yesAxioms, 2021
In this paper, the author considers twisted q-analogues of Catalan-Daehee numbers and polynomials by using p-adic q-integral on Zp. We derive some explicit identities for those twisted numbers and polynomials related to various special numbers and ...
Dongkyu Lim
doaj   +1 more source

Harmonic numbers, Catalan's triangle and mesh patterns

open access: yes, 2012
The notion of a mesh pattern was introduced recently, but it has already proved to be a useful tool for description purposes related to sets of permutations. In this paper we study eight mesh patterns of small lengths. In particular, we link avoidance of
Kitaev, Sergey, Liese, Jeffrey
core   +1 more source

On generalised catalan numbers

open access: yesDiscrete Mathematics, 1978
AbstractThe Catalan number Cn is defined to be 2nn(n+1). One of its occurrences is as the number of ways of bracketing a product of n+1 terms taken from a set with binary operation. In this note the corresponding result for a set with a k-ary operation is considered.
openaire   +2 more sources

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