The current official Radix seed node addresses are:
Asia-Pacific (South-East )
radix://rn1q2jt0jswv3lpct8tavr5tvlg2kv25f26x7w8kf6dz2hp4pu9cwq4we9tm5f@13.238.198.54
radix://rn1qvmp586ylq9e26n98zwyu9s5hdkq8j63t8l028x8wj4vqzk32dwzw0vrg58@54.66.161.181
radix://rn1q2fqfp9smlv3x5j4gca400j3mg9q63pgpu8hmd0xs0a3dgw5mv5s6jgznp3@3.106.155.92
radix://rn1qvcrg55mcgx6qgs7hj5arpvakvyzpc9pnp5ywhgcs4mvmp7ee4846p5zsdg@54.79.170.237
Asia-Pacific (South )
radix://rn1qg54vufz29c5hcwqxuv4pr60f4fsq6ds0qpa7qnrchdwnapkw6qcxymhy7l@3.109.57.223
radix://rn1qgf0tug4nmxfa7su8zsu8pejzq48eeglvxf8le09cuy0nsghzg44weacz2q@3.109.36.249
radix://rn1qfcl8ml7vm2gnyvm6tslmemrjmds6apajrk3vvyl4the0wsm0mkvjrjgtl2@65.0.241.14
radix://rn1qd4nnpfkafpljwt8xmvk5ksqy6cn7n3j6t2pcqrx4p2h6drt9qqksn8m94r@3.108.213.235
EU (West )
radix://rn1qthu8yn06k75dnwpkysyl8smtwn0v4xy29auzjlcrw7vgduxvnwnst6derj@99.80.126.26
radix://rn1qtk3g0a2ra663wyua0l4720vfzdje9uqsdzgzjet5w9dhspkaywnjal6dv6@52.49.146.20
radix://rn1qgvg5c20ude9cwxuxenrltemtw5zsg6n879kguwy0cx4mzq5plqg532l2xf@34.242.56.73
radix://rn1q040l0vqzuglnj6t5ffue3nacnj30h0thyrses0f5cc0n2fvx4wtknv2t7y@54.74.152.104
US (East )
radix://rn1qvw5v4w8llexz99uc9gmeh47qp2h9ax2y3aewm5e6vj5sdx8uuph2vfuvg3@3.221.232.135
radix://rn1qtq336a2nn2269fjes53pynwlytrv0katm6uzlfcyl6m7yscac5g7mh8prw@3.220.101.80
radix://rn1qwa45jjf40vuf9xlq85xym86yegnm95h3g8d4lul5hskrws9gm6ykyx7hsf@3.214.160.245
radix://rn1qvv0uljlqdsmed4kwjqr56sqkgcl8jer3z7w68ssfele3e4cz6uzugfjf0h@44.194.199.37
Source: Getting Started