On Ulam Stability of a Generalized Delayed Differential Equation of Fractional Order

Abstract We investigate Ulam stability of a general delayed differential equation fractional order. provide formulas showing how to generate the exact solutions using functions that satisfy it only approximately. Namely, approximate solution $$\phi $$ ? generates as pointwise limit sequence $$\varLambda ^n\phi ? n with some integral (possibly, nonlinear) operator . estimate speed convergence and distance between those solutions. Moreover, we exemplary calculations, involving Chebyshev Bielecki norms semigauges, could help obtain reasonable outcomes for such estimations in particular cases. The main tool is Diaz–Margolis fixed point alternative.