ON EXTENSION PROPERTY OF CANTOR-TYPE SETS

We suggest a new approach to prove the dominating norm property for spaces of Whitney functions, based on the estimation of least deviation of polynomials on Cantor-type sets. In this way we prove that the generalized Cantor sets of finite type and logarithmic dimension 1 have the extension property, since by Tidten-Vogt characterization a compact set K has the extension property iff the space has the property DN.