Robtex

Up: 72.255.128.0/17
Can't show all results, try to descend to a more specific CIDR
Down left: 72.255.128.0/19
Down right: 72.255.160.0/19

IP	Type	Hostname
72.255.144.136	A	zixvpm.spearehospital.org
72.255.147.65	PTR	72-255-147-65.client.stsn.net
72.255.147.66	PTR	72-255-147-66.client.stsn.net
72.255.147.67	PTR	72-255-147-67.client.stsn.net
72.255.147.131	PTR	72-255-147-131.client.stsn.net
72.255.147.195	PTR	72-255-147-195.client.stsn.net
72.255.149.1	PTR	72-255-149-1.client.stsn.net
72.255.162.129	PTR	72-255-162-129.client.stsn.net
72.255.172.0	PTR	72-255-172-0.client.stsn.net
72.255.172.1	PTR	72-255-172-1.client.stsn.net
72.255.172.3	PTR	72-255-172-3.client.stsn.net
72.255.175.66	PTR	72-255-175-66.client.stsn.net
72.255.175.130	PTR	72-255-175-130.client.stsn.net
72.255.181.0	PTR	72-255-181-0.client.stsn.net
72.255.181.2	PTR	72-255-181-2.client.stsn.net
72.255.181.3	PTR	72-255-181-3.client.stsn.net
72.255.181.64	PTR	72-255-181-64.client.stsn.net
72.255.181.65	PTR	72-255-181-65.client.stsn.net
72.255.181.66	PTR	72-255-181-66.client.stsn.net
72.255.181.194	PTR	72-255-181-194.client.stsn.net
72.255.182.3	A	www.drwahl.me
72.255.182.21	A	www.drwahl.me
72.255.183.3	PTR	72-255-183-3.client.stsn.net
72.255.183.64	PTR	72-255-183-64.client.stsn.net
72.255.183.65	PTR	72-255-183-65.client.stsn.net
72.255.183.128	PTR	72-255-183-128.client.stsn.net
72.255.183.195	PTR	72-255-183-195.client.stsn.net
72.255.187.1	PTR	72-255-187-1.client.stsn.net
72.255.187.2	PTR	72-255-187-2.client.stsn.net
72.255.187.129	PTR	72-255-187-129.client.stsn.net
72.255.187.130	PTR	72-255-187-130.client.stsn.net
72.255.187.192	PTR	72-255-187-192.client.stsn.net
72.255.187.195	PTR	72-255-187-195.client.stsn.net