Robtex

Up: 72.13.80.0/23
Can't show all results, try to descend to a more specific CIDR
Down left: 72.13.81.0/25
Down right: 72.13.81.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
72.13.81.2	A+PTR	ns2.egihosting.com
72.13.81.3	A+PTR	san-01.egihosting.com
72.13.81.19	A+PTR	livesupport.egihosting.com
72.13.81.20	PTR	smtp.egihosting.com
72.13.81.21	A	firewall.egihosting.com
72.13.81.25	PTR	stats.egihosting.com
72.13.81.27	PTR	ns3.egihosting.com
72.13.81.29	A+PTR	billing.egihosting.com
72.13.81.34	A+PTR	fmt01.egihosting.com
72.13.81.66	PTR	wall.missingpacket.com
72.13.81.90	PTR	1.fm
72.13.81.130	A	ikanyule.com
72.13.81.139	A	www.gansunet.com
72.13.81.141	A	qz49.com
72.13.81.141	A	www.cqhlkg.com
72.13.81.142	A	elu123.com
72.13.81.142	A	ip191.cn
72.13.81.142	A	sg.fyplay.com
72.13.81.154	PTR	nest.miniyard.net
72.13.81.173	A	yqkja.com
72.13.81.174	A	svdfq.com
72.13.81.180	A	bb.1.fm
72.13.81.186	PTR	firefly.encrypted.net
72.13.81.186	A	jimandnancy.org
72.13.81.186	A	mail.hosed.org
72.13.81.190	PTR	firefly.hosed.org
72.13.81.218	A+PTR	server143.egihosting.com
72.13.81.226	PTR	mail.spacialaudio.com
72.13.81.226	A	appreviewall.com
72.13.81.226	A	smtp.spacialcast.com
72.13.81.234	PTR	mail.spacial.com
72.13.81.243	PTR	sam-243-dance.1.fm
72.13.81.244	PTR	sam-244-club.1.fm
72.13.81.245	PTR	sam-245-top40.1.fm
72.13.81.246	PTR	sam-246-80s.1.fm
72.13.81.247	PTR	sam-247-90s.1.fm
72.13.81.248	PTR	sam-248-thegayway.1.fm
72.13.81.249	PTR	sam-249-flashback.1.fm