Pr (the tld of Puerto Rico) is a domain controlled by five domain name servers at nic.pr, denic.de and pch.net having a total of six IP numbers. Some of them are on the same IP network.
Ch.pr, pro.pr, org.pr, alumni.pr, uprr.pr and at least 44 other hosts share name servers with this domain. Vg.pr, es.pr, jm.pr, isla.pr, eu.pr and at least 37 other hosts share name servers under another name with this domain. Redistribucionelectoral2010.pr, wyeth.pr, logon.pr, rumsofpuertorico.pr, hardrock.pr and at least 94 other hosts are subdomains to this domain. Sky.pr, quehacer.pr, compusa.pr, visapassfirst.pr, oliver-exterminating.pr and at least 94 other hosts are hosts under this domain. Pr.com, pr.by, pr.cc, pr.cm, pr.ag and at least 114 other hosts are similar domain names.
Also check www.pr.
There are about fifty domains that use the name server pr-ns.anycast.pch.net.
pr-dns.denic.de, descartes.nic.pr, golomb.nic.pr, pascal.nic.pr and pr-ns.anycast.pch.net together, hereafter referred to as "name server group 1", (example: cn.pr, est.pr and com.pr ).134.202.4.100 (example: tc.pr, en.pr and mx.pr ).There are about fifty domains that use name server group 1.
134.202.4.100 (example: ms.pr, de.pr and lc.pr ).134.202.1.120 (example: prof.pr and ac.pr ).Six of the about fifty domains that use the name server descartes.nic.pr point to the IP number 134.202.1.120 (example: ut.pr ).