Robtex

Up: 72.232.16.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 72.232.20.0/23
Down right: 72.232.22.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
72.232.20.1	PTR	ns3.ltdomains.com
72.232.20.2	PTR	ns3.ltdomains.com
72.232.20.62	PTR	server.hostgood.com.br
72.232.20.74	PTR	74.20.232.72.static.reverse.ltdomains.com
72.232.20.101	A	101.20.232.72.static.reverse.ltdomains.com
72.232.20.122	A	printingindallas.com
72.232.20.122	A	rehearsaldallas.com
72.232.20.122	A	mail.rehearsaldallas.com
72.232.20.125	A	austintxprinting.com
72.232.20.125	A	mail.austintexasprinting.com
72.232.20.125	A	austintexasprinting.com
72.232.20.126	A	houstontexasprinting.com
72.232.20.131	A	131.20.232.72.static.reverse.ltdomains.com
72.232.20.146	PTR	146.20.232.72.static.reverse.ltdomains.com
72.232.20.149	A+PTR	149.20.232.72.static.reverse.ltdomains.com
72.232.20.154	PTR	154.20.232.72.static.reverse.ltdomains.com
72.232.20.167	A	167.20.232.72.static.reverse.ltdomains.com
72.232.20.169	PTR	169.20.232.72.static.reverse.ltdomains.com
72.232.20.176	A	176.20.232.72.static.reverse.ltdomains.com
72.232.20.194	A+PTR	194.20.232.72.static.reverse.ltdomains.com
72.232.20.207	PTR	207.20.232.72.static.reverse.ltdomains.com
72.232.20.214	A	214.20.232.72.static.reverse.ltdomains.com
72.232.20.215	A	215.20.232.72.static.reverse.ltdomains.com
72.232.20.216	A	216.20.232.72.static.reverse.ltdomains.com
72.232.20.221	PTR	exp4.tanainternet.com
72.232.20.223	A	mx2.kana-united.com
72.232.20.235	PTR	72.232.20.235.theunmetered.com
72.232.21.8	A	8.21.232.72.static.reverse.ltdomains.com
72.232.21.9	A	9.21.232.72.static.reverse.ltdomains.com
72.232.21.11	PTR	easycyberonline.com
72.232.21.13	PTR	freeglobalforyou.com
72.232.21.24	A	24.21.232.72.static.reverse.ltdomains.com
72.232.21.50	A	ns2.domesticmisfits.net
72.232.21.66	A+PTR	66.21.232.72.static.reverse.ltdomains.com
72.232.21.96	A	96.21.232.72.static.reverse.ltdomains.com
72.232.21.97	A	97.21.232.72.static.reverse.ltdomains.com
72.232.21.100	A	mail.experiencia4x4.com
72.232.21.102	A	102.21.232.72.static.reverse.ltdomains.com
72.232.21.106	PTR	mr01.losethespam.com
72.232.21.107	PTR	mr01.losethespam.com
72.232.21.108	PTR	mr01.losethespam.com
72.232.21.109	PTR	mr01.losethespam.com
72.232.21.110	PTR	mr01.losethespam.com
72.232.21.118	A	118.21.232.72.static.reverse.ltdomains.com
72.232.21.121	A	121.21.232.72.static.reverse.ltdomains.com
72.232.21.127	A	127.21.232.72.static.reverse.ltdomains.com
72.232.21.139	PTR	139.21.232.72.static.reverse.ltdomains.com
72.232.21.144	A	144.21.232.72.static.reverse.ltdomains.com
72.232.21.149	A	149.21.232.72.static.reverse.ltdomains.com
72.232.21.151	A	151.21.232.72.static.reverse.ltdomains.com
72.232.21.169	A	169.21.232.72.static.reverse.ltdomains.com
72.232.21.172	A	172.21.232.72.static.reverse.ltdomains.com
72.232.21.208	A	208.21.232.72.static.reverse.ltdomains.com
72.232.21.225	A	225.21.232.72.static.reverse.ltdomains.com
72.232.21.230	A	230.21.232.72.static.reverse.ltdomains.com
72.232.21.242	A	242.21.232.72.static.reverse.ltdomains.com
72.232.22.95	A	95.22.232.72.static.reverse.ltdomains.com
72.232.22.123	A+PTR	123.22.232.72.static.reverse.ltdomains.com
72.232.22.125	A	ns2.securityserver.org
72.232.22.126	A	126.22.232.72.static.reverse.ltdomains.com
72.232.22.138	PTR	u2.nposerver.net
72.232.22.138	A	www.gamepirate.com
72.232.22.138	A	gamepirate.com
72.232.22.140	PTR	ns3.nposerver.net
72.232.22.140	A	campusanyware.net
72.232.22.140	A	0disaster.com
72.232.22.142	PTR	142.22.232.72.static.reverse.ltdomains.com
72.232.22.165	PTR	ip006.mikrokap.com
72.232.22.194	PTR	194.22.232.72.reverse.drabs.com
72.232.22.194	A	loosediamonds.pro
72.232.22.194	A	ns1.yetanotherhost.com
72.232.22.195	PTR	195.22.232.72.reverse.drabs.com
72.232.22.196	PTR	196.22.232.72.reverse.drabs.com
72.232.22.196	A	approvedcashadvance.net
72.232.22.196	A	ccwf.net
72.232.22.197	PTR	197.22.232.72.reverse.drabs.com
72.232.22.198	PTR	198.22.232.72.reverse.drabs.com
72.232.22.201	PTR	webhostingstuff.com
72.232.22.203	A	racing-guys.com
72.232.22.205	PTR	tinycounter.com
72.232.22.214	PTR	214.22.232.72.static.reverse.ltdomains.com
72.232.22.217	PTR	217.22.232.72.static.reverse.ltdomains.com
72.232.22.226	PTR	mx2.global-nameservers.com
72.232.22.226	A	mail.ktljcw.com
72.232.22.226	A	mail.localanalytics.info
72.232.22.234	PTR	234.22.232.72.static.reverse.ltdomains.com
72.232.22.234	A	cuteflashgames.com
72.232.22.234	A	freegamesjungle.com
72.232.22.242	A	242.22.232.72.static.reverse.ltdomains.com
72.232.22.243	A+PTR	243.22.232.72.static.reverse.ltdomains.com
72.232.22.243	A	ns2.ilhahost.com.br
72.232.22.250	A	mail.cevo.com
72.232.23.1	A+PTR	offerserv2.123greetings.biz
72.232.23.13	A	offerserv14.123greetings.biz
72.232.23.67	PTR	67.23.232.72.static.reverse.ltdomains.com
72.232.23.103	A	103.23.232.72.static.reverse.ltdomains.com
72.232.23.114	A	114.23.232.72.static.reverse.ltdomains.com
72.232.23.117	A	117.23.232.72.static.reverse.ltdomains.com
72.232.23.119	A	119.23.232.72.static.reverse.ltdomains.com
72.232.23.133	PTR	vps.mycohost.net
72.232.23.142	A	142.23.232.72.static.reverse.ltdomains.com
72.232.23.171	A	171.23.232.72.static.reverse.ltdomains.com
72.232.23.174	A	174.23.232.72.static.reverse.ltdomains.com
72.232.23.194	A+PTR	savvis.ltstatus.com
72.232.23.195	PTR	ns1.layeredtech.com
72.232.23.196	A+PTR	savvis.ntp.layeredtech.com
72.232.23.196	A	ntp.layeredtech.com
72.232.23.201	PTR	savvis.rwhois.layeredtech.com
72.232.23.201	A	rwhois.layeredtech.com
72.232.23.203	A+PTR	savvis.speedtest.layeredtech.com
72.232.23.203	A	speedtest.layeredtech.com
72.232.23.219	PTR	savvis.radius.layeredtech.com
72.232.23.219	A	radius.layeredtech.com
72.232.23.221	PTR	ns1.ltdomains.com