Functional Equations and Inequalities

On the Stability of a Functional Equation for Generalized Trigonometric Functions.- Some Notes on Two-Scale Difference Equations.- Some Demand Functions in a Duopoly Market with Advertising.- Solutions of a Functional Inequality in a Special Class of Functions.- On Dependence of Lipschitzian Solutions of Nonlinear Functional Inequality on an Arbitrary Function.- The Problem of Expressibility in Some Extensions of Free Groups.- On a Pythagorean Functional Equation Involving Certain Number Fields.- On a Conditional Cauchy Functional Equation Involving Cubes.- Hyers-Ulam Stability of Hosszú’s Equation.- The Functional Equation of the Square Root Spiral.- On the Superstability of the Functional Equation f(xy)=f(x)y.- Replicativity and Function Spaces.- Normal Distributions and the Functional Equation f(x+y) g(x-y) = f(x)f(y)g(x)g(-y).- On the Polynomial-Like Iterative Functional Equation.- Distribution of Zeros and Inequalities for Zeros of Algebraic Polynomials.- A Functional Definition of Trigonometric Functions.- A Qualitative Study of Lobachevksy’s Complex Functional Equation.- Smooth Solutions of an Iterative Functional Equation.- Set-Valued Quasiconvex Functions and their Constant Selections.- Entire Solutions of the Hille-type Functional Equation.- Ulam’s Problem, Hyers’s Solution — and to Where they Led.- A Separation Lemma for the Construction of Finite Sums Decompositions.- Aleksandrov Problem and Mappings which Preserve Distances.- On Some Subclasses of Harmonic Functions.