Robtex

Up: 72.51.24.0/22
Can't show all results, try to descend to a more specific CIDR
Down left: 72.51.26.0/24
Down right: 72.51.27.0/24
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
72.51.26.33	PTR	phdassessments.com
72.51.26.40	A	www.phdassessments.com
72.51.26.49	A	mail.netsecuria.com
72.51.26.49	A	mail.streetog.com
72.51.26.49	A	max-solutions.ca
72.51.26.87	PTR	lbc03.hcareers.com
72.51.26.97	A+PTR	gw.atx.com.mx
72.51.26.97	A	mail.calasanz.org.mx
72.51.26.98	A+PTR	mail.apizaco.gbsistemas.com
72.51.26.98	A	www.capamapizaco.gob.mx
72.51.26.98	A	mail.mabs.com.mx
72.51.26.99	PTR	web.apizaco.gbsistemas.com
72.51.26.101	PTR	48331a66.gbsistemas.com
72.51.26.104	A	nw.dogi.com.mx
72.51.26.105	A	gw.dogi.com.mx
72.51.26.106	A	mail.dogi.com.mx
72.51.26.107	A	bcast.dogi.com.mx
72.51.26.109	PTR	zimbra.boxflex.com.mx
72.51.26.110	A	mx.boxflex.com.mx
72.51.26.110	A	zimbra.boxflex.com.mx
72.51.26.110	A	110.boxflex.com.mx
72.51.26.133	PTR	mail5.plentyoffish.co.uk
72.51.26.134	PTR	pv-0001.pof.com
72.51.26.134	A	pv-0002.pof.com
72.51.26.211	A	ssl.gpsonextra.net
72.51.26.213	A	pine3.gpstream.net
72.51.26.213	A	pine2.gpstream.net
72.51.26.214	A	hotpgps2.gpstream.net
72.51.26.214	A	hotpgps3.gpstream.net
72.51.26.218	A	pgps7-2.gpstream.net
72.51.26.218	A	marvell-1.pgps.gpstream.net
72.51.26.218	A	marvell-2.pgps.gpstream.net
72.51.27.3	A+PTR	lb10.reinvent.com
72.51.27.4	A	lb11.reinvent.com
72.51.27.9	PTR	vmh1.reinvent.com
72.51.27.16	A	*.economictimes.calculatorloanrepayment.com
72.51.27.16	A	*.gdsz.calculatorloanrepayment.com
72.51.27.16	A	*.reverse.calculatorloanrepayment.com
72.51.27.50	A+PTR	services.reinvent.com
72.51.27.50	A	vpn.reinvent.com
72.51.27.51	A	*.venus.nitronet.net
72.51.27.51	A	a.ns.crowd9.net
72.51.27.55	PTR	ns1.parked-domains.net
72.51.27.60	A	18.157.172.184.hitfarm.com
72.51.27.60	A	*.180.68.hitfarm.com
72.51.27.60	A	*.www.apct.com
72.51.27.100	A	www.domainbrokers.com
72.51.27.126	A	wilshirefinancepartners.com
72.51.27.126	A	wilshirefp.com
72.51.27.140	PTR	kspecial.reinvent.com
72.51.27.210	A	expertbasics.com
72.51.27.247	A+PTR	my.ncolmail.com
72.51.27.247	A	mailserver2.ncolmail.com
72.51.27.253	A	www.wdadv.com
72.51.27.253	A	ncol.com
72.51.27.253	A	www.webdirectadvertising.com