Abstract
We consider two widths related to the notion of pseudo-dimension. The first is 
, which is defined in a similar way to Kolmogorov's width but replacing the linear dimension by the pseudo-dimension. can be bounded below by the second width 
, which is half of the length of the maximal edge of the 
-dimensional `coordinate' cube inscribed in the given set in a special way. We construct examples of sets for which the ratios 
(for 
) and 
(for a sufficiently large 
) are as large as desired. In terms of combinatorial dimension, the main result means that for any 
and any sufficiently large there is a set 
of dimension 
which cannot be approximated with respect to the uniform norm with accuracy 
by any set 
of dimension 
.