Simultaneous polynomial approximation in Beurling-Sobolev spaces via Blaschke products

Stéphane Charpentier, Nicolas Espoullier, Rachid Zarouf

Assuming that $\ddot{I}•(t)=o(t^2)$ as $t\to 0$, we establish a lemma on simultaneous polynomial approximation in Orlicz-Beurling-Sobolev spaces ${\ell }_a^{\ddot{I}}•$. These spaces, endowed with the…