Robtex

Up: 182.72.8.0/21
Can't show all results, try to descend to a more specific CIDR
Down left: 182.72.12.0/23
Down right: 182.72.14.0/23
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
182.72.12.50	PTR	nsg-static-050.12.72.182.airtel.in
182.72.12.50	A	mx2.praxistechnologies.net
182.72.12.82	PTR	nsg-static-082.12.72.182.airtel.in
182.72.12.98	PTR	nsg-static-098.12.72.182.airtel.in
182.72.12.100	PTR	seaworldship.com
182.72.12.100	PTR	skyworldair.com
182.72.12.100	PTR	tcspl-india.com
182.72.12.219	A+PTR	mail.verixo.net
182.72.12.220	A	mail.priyachemicals.co.in
182.72.12.220	A	mail.vxlindia.biz
182.72.12.220	A	mail1.priyagroup.com
182.72.13.32	PTR	nsg-static-032.13.72.182.airtel.in
182.72.13.220	PTR	nsg-static-220.13.72.182.airtel.in
182.72.14.69	PTR	nsg-static-069.14.72.182.airtel.in
182.72.14.194	PTR	nsg-static-194.14.72.182.airtel.in
182.72.14.210	PTR	nsg-static-210.14.72.182.airtel.in
182.72.14.215	PTR	nsg-static-215.14.72.182.airtel.in
182.72.14.218	PTR	nsg-static-218.14.72.182.airtel.in
182.72.14.218	A	mx.indostarcapital.com
182.72.15.9	PTR	nsg-static-009.15.72.182.airtel.in
182.72.15.60	PTR	nsg-static-060.15.72.182.airtel.in
182.72.15.99	PTR	nsg-static-099.15.72.182.airtel.in
182.72.15.137	PTR	fpaindia.org
182.72.15.138	PTR	fpaindia.org
182.72.15.138	A+PTR	mail.fpaindia.org
182.72.15.139	PTR	fpaindia.org
182.72.15.140	PTR	fpaindia.org
182.72.15.141	PTR	fpaindia.org
182.72.15.142	PTR	fpaindia.org
182.72.15.162	PTR	mail1.soft-techinfosystems.com
182.72.15.162	A	mail.rrmc-navnitmotors.in
182.72.15.162	A	mail.shreenathmotors.com
182.72.15.163	PTR	nsg-static-163.15.72.182.airtel.in
182.72.15.164	PTR	mail1.soft-techinfosystems.com
182.72.15.182	PTR	nsg-static-182.15.72.182.airtel.in