A new branch router will not become an EIGRP neighbor

A contractor installed R3 at a new branch and connected it to R1 on Gi0/0/1 (10.0.13.0/24, R1 is .1, R3 is .3). The config came from a template the contractor uses at other customers. R1 already has a working EIGRP AS 100 neighbor, R2, on Gi0/0/0. Ping between 10.0.13.1 and 10.0.13.3 works, but R1 has no route to the branch LAN 10.3.0.0/24 and the branch cannot reach anything beyond R1.