activity
20142026
most citedSome properties of Zumkeller numbers and -layered numbers

6 citations · 6 across the 12 of their papers we have counts for

collaborators

19 papers

math.CO2026

Graph binomial coefficients and a positivity conjecture of Guo and Krattenthaler

Madjid Mirzavaziri, Daniel Yaqubi

We investigate Conjecture 7.4 of Guo and Krattenthaler \cite{GK}, which predicts that for every positive integer , the polynomial \[ P_n(q) = \frac{(1-q)^2}{(1-q^{10n-1})(1-q^{1…

math.CO2026

Riordan Arrays and Shifted Hankel Determinants of OEIS A005773

Daniel Yaqubi, Madjid Mirzavaziri

We study two Riordan arrays associated with the Motzkin-prefix sequence (\href{https://oeis.org/A005773}{OEIS A005773}). By connecting their production matrices through a simple bo…

math.CO2026

Cyclic Latin Eulerian Numbers

Madjid Mirzavaziri, Daniel Yaqubi

We introduce the directed cyclic difference inventory to study Latin Eulerian numbers restricted to row-reorderings of the cyclic Latin square, offering an orient…

math.CO2026

Latin Eulerian Numbers

Madjid Mirzavaziri, Daniel Yaqubi

We introduce \emph{Latin Eulerian numbers} $\LE{n\atop k_1,\dots,k_n}$, a multivariate refinement of classical Eulerian numbers counting order- Latin squares by column ascents.…

math.GM2026

A Combinatorial Problem in Cinema Seating

Madjid Mirzavaziri, Daniel Yaqubi

We address a problem concerning cinema audiences: ``A cinema has seats numbered from to , and there are people with tickets numbered from to . People enter th…

math.CO2026

Prime and Touchard Congruences of Mixed-Type Bell Numbers

Daniel Yaqubi, Madjid Mirzavaziri

This paper establishes a comprehensive combinatorial and arithmetic framework for mixed Stirling and mixed Bell numbers, bridging partition structures, Touchard polynomials, and pr…

math.CO2026

Arithmetic Properties of Mixed Stirling Numbers of the second kind

Daniel Yaqubi, Madjid Mirzavaziri

We investigate the mixed Stirling numbers of the second kind, , which count partitions of distinct elements into unlabeled and labeled non-e…

math.CO2026

On the Graphical -Stirling Numbers of the First Kind for Specific Graph Families

Daniel Yaqubi, Madjid Mirzavaziri

This paper investigates the \textbf{graphical -Stirling numbers of the first kind}, denoted by $\str{G}{k}$, which enumerate partitions of a vertex set into disjoint…

math.NT2020★ 6 cited

Some properties of Zumkeller numbers and -layered numbers

Pankaj Jyoti Mahanta, Manjil P. Saikia, Daniel Yaqubi

Generalizing the concept of a perfect number is a Zumkeller or integer perfect number that was introduced by Zumkeller in 2003. The positive integer is a Zumkeller number if it…

math.CO2020

Some results on average of Fibonacci and Lucas sequences

Daniel Yaqubi, Amirali Fatehizadeh

In this paper, we discuss about some results on average of Fibonacci and Lucas sequences that may be found in the OEIS code A111035.

math.CO2019

Mixed coloured permutations

Beáta Bényi, Daniel Yaqubi

In this paper we introduce mixed coloured permutation, permutations with certain coloured cycles, and study the enumerative properties of these combinatorial objects. We derive the…

math.CO2018

Mixed restricted Stirling numbers

Somaya Barati, Beáta Bényi, Abbas Jafarzadeh +1

In this note we investigate mixed partitions with extra condition on the sizes of the blocks. We give a general formula and the generating function. We consider in more details a s…

math.CO2018

Some determinants of path generating functions, II

Christian Krattenthaler, Daniel Yaqubi

We evaluate Hankel determinants of matrices in which the entries are generating functions for paths consisting of up-steps, down-steps and level steps with a fixed starting point b…

math.GM2017

Lattice paths inside a table, II

Daniel Yaqubi, Mohammad Farrokhi Derakhshandeh Ghouchan, Mohamad Zamani khademanlu

Consider an table and latices paths in such that each step , or . The number of paths from the -blank…

math.CO2017

Some divisibility properties of binomial coefficients

Daniel Yaqubi, Madjid Mirzavaziri

In this paper, we gave some properties of binomial coefficient.

math.CO2015

Spanning k-ended trees of 3-regular connected graphs

Hamed Ghasemian Zoeram, Daniel Yaqubi

A tree is called k-ended tree if it has at most k leaves, where a leaf is a vertex of degree one. In this paper we prove that every 3-regular connected graph with n vertices such t…

math.CO2015

The Twelvefold way, the non-intersecting circles problem, and partitions of multisets

Toufik Mansour, Madjid Mirzavaziri, Daniel Yaqubi

Let be a non-negative integer and be a multi-set with not necessarily distinct members, where . We denote by $Δ(n,A)…

math.CO2014

Mixed r-stirling numbers of the second kind

Daniel Yaqubi, Madjid Mirzavaziri, Yasin Saeednezhad

The Stirling number of the second kind counts the number of ways to partition a set of labeled balls into non-empty unlabeled cells. As an extension of this, we…

math.CO2014

Some results on ordered and unordered factorization of a positive integers

Daniel Yaqubi, Madjid Mirzavaziri

As a well-known enumerative problem, the number of solutions of the equation with in positive integers is $Π(m,k)=\sum_{i=0}^kΠ(m-k,i…