Use the Sequencer tool to create sequences and to assign incremental numbers to parts.
You can define several sequences for different purposes, and a part can belong to several sequences at the same time. For example, you can create erection sequences to define the order in which to erect parts.
Sequencer works by assigning a sequence number to a user-defined attribute (UDA) of a part. If you want to view and modify the sequence numbers afterwards, you must first create a new user-defined attribute to which you assign the sequence numbers.
Sequencer does not work for objects that are inside a reference model.