Table of Contents
| Cover pages v38n1 | |
| Vasile Staicu | i-ii |
| Optimization problems in classes of rearrangements | |
| Feyissa Kebede | 1 - 16 |
| About the efficiency behavior of the Portuguese manufacturing firms during the financial crisis | |
| Kelly Murillo, Eugénio Rocha, Joaquim Ramalho | 17 - 44 |
| Finding the Fundamental Solutions of the Pell Equation $% x^{2}-dy^{2}=\pm 1$ by determining the Right Neighbor of $F=(d,0,-1)$ | |
| Ahmet Tekcan, Gül Karadeniz Gözeri | 45-58 |
| Adaptation of a Cryptosystem Based on the Arithmetic of Finite Fields to Elliptic Curves | |
| Ounasser Abid, omar Khadir | 59 - 68 |
| The Smarandache vertices of comaximal graph of a commutative ring | |
| Elham Mehdi-Nezhad, Amir Massoud Rahimi | 69 - 82 |
| In memoriam: Ioan I Vrabie | |
| Ovidiu Carja | 83-85 |
ISSN: 2182-567X