It is shown that Jackson type inequality fails in the Orlicz classes φ(L) if φ(x) differs essentially from a power function of any order.
@article{urn:eudml:doc:44391, title = {On Jackson type inequality in Orlicz classes.}, journal = {Revista Matem\'atica de la Universidad Complutense de Madrid}, volume = {14}, year = {2001}, pages = {395-404}, zbl = {1004.42002}, mrnumber = {MR1871304}, language = {en}, url = {http://dml.mathdoc.fr/item/urn:eudml:doc:44391} }
Runovski, Konstantin. On Jackson type inequality in Orlicz classes.. Revista Matemática de la Universidad Complutense de Madrid, Tome 14 (2001) pp. 395-404. http://gdmltest.u-ga.fr/item/urn:eudml:doc:44391/