JENSEN'S FUNCTIONAL AND POLYNOMIALS

We investigate some estimates of the {sc Jensen}'s functional $$ J(p)= intlimits_0^{2pi }log | p ( e^{i heta }) |, frac{{ m d} heta }{2pi },,$$ if the polynomial $p(z)$ has a concentration at low degrees measured by $ell_2$-norm. We consider the constants involved, both from a theoretical and a numerical point of view.