Robtex

Up: 72.131.128.0/17
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Down left: 72.131.128.0/19
Down right: 72.131.160.0/19

IP	Type	Hostname
72.131.136.1	PTR	mta-72-131-136-1.wi.rr.com
72.131.136.64	PTR	mta-72-131-136-64.wi.rr.com
72.131.136.130	PTR	mta-72-131-136-130.wi.rr.com
72.131.136.193	PTR	mta-72-131-136-193.wi.rr.com
72.131.155.2	PTR	mta-72-131-155-2.wi.rr.com
72.131.155.3	PTR	mta-72-131-155-3.wi.rr.com
72.131.155.192	PTR	mta-72-131-155-192.wi.rr.com
72.131.155.193	PTR	mta-72-131-155-193.wi.rr.com
72.131.160.137	PTR	mta-72-131-160-137.wi.rr.com
72.131.168.1	PTR	mta-72-131-168-1.wi.rr.com
72.131.168.194	PTR	mta-72-131-168-194.wi.rr.com
72.131.168.195	PTR	mta-72-131-168-195.wi.rr.com
72.131.177.3	PTR	mta-72-131-177-3.wi.rr.com
72.131.177.129	PTR	mta-72-131-177-129.wi.rr.com
72.131.177.130	PTR	mta-72-131-177-130.wi.rr.com
72.131.177.194	PTR	mta-72-131-177-194.wi.rr.com