With equations , and , the formula can be approximated by {TAIL ~ the equation} ##EQU11## for {HEAD ~ i, j}  
With equations , and , the formula can be approximated by { TAIL ~ the equation } # # EQU11 # # for { HEAD ~ i , j }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH