Utilitas Algorithmica (UA)
ISSN: xxxx-xxxx (print)
Utilitas Algorithmica (UA) is a premier, open-access international journal dedicated to advancing algorithmic research and its applications. Launched to drive innovation in computer science, UA publishes high-impact theoretical and experimental papers addressing real-world computational challenges. The journal underscores the vital role of efficient algorithm design in navigating the growing complexity of modern applications. Spanning domains such as parallel computing, computational geometry, artificial intelligence, and data structures, UA is a leading venue for groundbreaking algorithmic studies.
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 77-89
- Published: 30/11/2010
Given a graph \( G = (V, E) \), a set \( W \subseteq V \) is said to be a resolving set if for each pair of distinct vertices \( u, v \in V \), there is a vertex \( x \) in \( W \) such that \( d(u, x) \neq d(v, x) \). The resolving number of \( G \) is the minimum cardinality of all resolving sets. In this paper, a condition is imposed on resolving sets and a conditional resolving parameter is studied for grid-based networks.
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 65-75
- Published: 30/11/2011
Let \( G = (V, E) \) be a graph. A vertex labeling \( f: V \to \mathbb{Z}_2 \) induces an edge labeling \( f^*: E \to \mathbb{Z}_2 \) defined by \( f^*(xy) = f(x) + f(y) \) for each \( xy \in E \). For each \( i \in \mathbb{Z}_2 \), define \( v_f(i) = |f^{-1}(i)| \) and \( e_f(i) = |{f^*}^{-1}(i)| \). We call \( f \) friendly if \( |v_f(1) – v_f(0)| \leq 1 \). The full friendly index set of \( G \) is the set of all possible values of \( e_f(1) – e_f(0) \), where \( f \) is a friendly labeling. In this paper, we study the full friendly index set of the wheel \( W_n \), the tensor product of paths \( P_2 \) and \( P_n \), i.e., \( P_2 \otimes P_n \), and the double star \( D(m, n) \).
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 59-64
- Published: 30/11/2011
The detour order of a graph \( G \), denoted \( \tau(G) \), is the order of a longest path in \( G \). A partition \( (A, B) \) of \( V(G) \) such that \( \tau(\langle A \rangle) \leq a \) and \( \tau(\langle B \rangle) \leq b \) is called an \( (a, b) \)-partition of \( G \). A graph \( G \) is called \( \tau \)-\textit{partitionable} if \( G \) has an \( (a, b) \)-partition for every pair \( (a, b) \) of positive integers such that \( a + b = \tau(G) \).
The well-known Path Partition Conjecture states that every graph is \( \tau \)-partitionable. Motivated by the recent result of Dunbar and Frick [6] that if every \( 2 \)-connected graph is \( \tau \)-partitionable, then every graph is \( \tau \)-partitionable, we show that the Path Partition Conjecture is true for a large family of \( 2 \)-connected graphs with certain ear-decompositions. Also, we show that a family of \( 2 \)-edge-connected graphs with certain ear-decompositions is \( \tau \)-partitionable.
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 43-58
- Published: 30/11/2011
he problem of determining the collaboration graph of co-authors of Paul Erdos is a challenging task. Here we take up this problem for the case of Rolf Nevanlinna Prize Winners. Even though the number of prize winners as of date is 7, the collaboration graph has 20 vertices and 41 edges and possesses several interesting properties. In this paper, we have obtained this graph and determined standard graph parameters for the graph as well as its complement besides probing its structural properties. Several new results were obtained.
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 33-42
- Published: 31/05/2010
The topological descriptor Wiener index, named after the chemist Harold Wiener, is defined as half the sum of the distances between every pair of vertices of a graph. A lot of research has been devoted to finding the Wiener index by brute force method. In this paper, we compute the Wiener index of chemical structures such as sodium chloride and benzenoid without using a distance matrix.
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 23-31
- Published: 30/11/2011
A graph \( G(p, q) \) is said to be total edge bimagic with two common edge counts \( k_1 \) and \( k_2 \) if there exists a bijection \( f: V(G) \cup E(G) \to \{1, 2, \ldots, p + q\} \) such that for each edge \( uv \in E(G) \), \( f(u) + f(v) + f(uv) = k_1 \) or \( k_2 \).
A total edge-bimagic graph is called super edge-bimagic if \( f(V(G)) = \{1, 2, \ldots, p\} \). In this paper, we define new types of super edge-bimagic labeling and prove some interesting results related to super edge-bimagic labeling. Also, its relationship with cordial labeling is studied.
- Research article
- Full Text
- Journal of Combinatorial Mathematics and Combinatorial Computing
- Volume 079
- Pages: 3-22
- Published: 30/11/2011
Trust is one of the most important means to improve the reliability of computing resources provided in a cloud environment and it plays an important role in commercial cloud environments. Trust is the estimation of the capability of a cloud resource in completing a task based on reputation, identity, behavior, and availability in the context of a distributed environment. It helps customers in the selection of appropriate resources in heterogeneous cloud infrastructure. The cloud computing depends on the following QoS parameters such as reliability, availability, scalability, security, and past behavior of the cloud resources.
This paper introduces a novel trust model to evaluate cloud resources of IaaS (Infrastructure as a Service) providers by means of Trust Resource Broker. The Trust Resource Broker selects trustworthy cloud resources based on the requirements of customers. The proposed trust model evaluates the trust value of the resources based on the identity as well as behavioral trust. The proposed model applies the QoS metrics suitable for cloud resources. The results of the experiments show that the proposed trust model selects the most reliable resources in a cloud environment.
- Research article
- Full Text
- Ars Combinatoria
- Volume 102
- Pages: 517-528
- Published: 31/10/2011
By the classical method for obtaining the values of the Riemann zeta-function at even positive integral arguments, we shall give some functional equational proof of some interesting identities and recurrence relations related to the generalized higher-order Euler and Bernoulli numbers attached to a Dirichlet character \(\chi\) with odd conductor \(d\), and shall show an identity between generalized Euler numbers and generalized Bernoulli numbers. Finally, we remark that any weighted short-interval character sums can be expressed as a linear combination of Dirichlet \(L\)-function values at positive integral arguments, via generalized Bernoulli (or Euler) numbers.
- Research article
- Full Text
- Ars Combinatoria
- Volume 102
- Pages: 505-515
- Published: 31/10/2011
A point set \(X\) in the plane is called a k-distance set if there are exactly \(k\) different distances between two distinct points in \(X\). We classify \(11\)-point \(5\)-distance sets.
- Research article
- Full Text
- Ars Combinatoria
- Volume 102
- Pages: 493-504
- Published: 31/10/2011
In this paper, we define the self-inverse sequences related to Sheffer sets and give some interesting results of these sequences. Moreover, we study the self-inverse sequences related to the Laguerre polynomials of order \(a\).




