On the best Ulam constant of the linear differential operator with constant coefficients

Alina-Ramona Baias, Dorian Popa

The linear differential operator with constant coefficients $$D(y)=y^{(n)}+a_1{y}^{(n-1)}+\dots +a_{n}y,y\in {\mathcal{C}}^n(\mathbb{R},X)$$ acting in a Banach space $X$ is Ul…