A priority vector for {TAIL ~ the combination} of requesters has a sequential list of {HEAD ~ requester identifiers} 
A priority vector for { TAIL ~ the combination } of requesters has a sequential list of { HEAD ~ requester identifiers }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD