You can setup sequenced order numbers by enabling the "Store Specific Order Number" setting. Normally this is turned on for those who tag so they can easily match everything together. It's also great for businesses that rack by order number.

This will add a sequenced order number on top of assembly receipts. The number matches the sequence in which orders have been detailed and is tracked separately per store. Numbers go from 10001-99999 and start over from 10001 once when order 99999 has been created.

Normally the sequence number is at the bottom of the receipt but you can enable "Store Specific Order Number Top Of Ticket" so it goes to the top of the receipt.

Store Specific Order Number can be enabled under Settings - > Business Settings -> System Settings -> Company Tab

Store Specific Order Number Top Of Ticket can be enabled under Settings -> Business Settings -> System Settings -> Receipt Tab