Here, {TAIL ~ 13 stage counter} of {HEAD ~ counters} X0 to X12, among the counters X0 to X13, corresponds to n stage counters according to the present invention 
Here , { TAIL ~ 13 stage counter } of { HEAD ~ counters } X0 to X12 , among the counters X0 to X13 , corresponds to n stage counters according to the present invention
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH