Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
Name the builder numbers with RR class of a1 and year less than 1916

### Inputs:
table_name: table, columns: ['Year', 'RR class', 'RR Nos.', 'Builder', 'Builder Nos.', 'GWR/BR Nos.']

### Response:
SELECT Builder Nos. FROM table WHERE RR class = a1 AND Year < 1916