Figure 1

(a) A network where its nodes are ranked in decreasing order of their degree and (b) the degree kr of node r and the number of links \({k}_{r}^{+}\) that node r has with nodes of higher rank. (c) The same network where the three top ranked nodes form a core and (d) number of links \({K}_{r}^{+}(3)\) that node r has with the any of these three top ranked nodes.