 $ C_0 =0$ and $$C_0= \sum_{i,j=0}^{m}E_{ij}E_{ji}- \sum_{\bar{k},\bar{l}=m+0}^{m+n}E_{\bar{k}\bar{l}}E_{\bar{l}\bar{k}} +\sum_{i=0}^{m}\sum_{\bar{k}=m+0}^{m+n}(E_{\bar{k}i}E_{i\bar{k}}- E_{i\bar{k}}E_{\bar{k}i})