Present paper cluster distribution in a log 10(L_X) versus redshift diagram. The two vertical green lines separate the most luminous, luminous, and moderately luminous clusters. Black disks are C1 clusters, red disks are C2 clusters, blue disks are C3 clusters. We also show as black, red, and blue curves the detection limit of the lowest X-ray flux cluster in C1, C2, and C3 classes.