Does Doc seq defined at receivables module level apply to all transaction types including receipts?

Summary:

Hi, Our Client, has defined gapless document sequencing for transaction types (Invoices, CM, DM, Adjustments) at receivables module level in Manage Receivables document sequencing setup with an expectation that sequencing will apply only for transactions types (Invoice, CM, DM/Adjustments) but when we saw there was missing in sequence in transactions, we have identified that this sequence is followed by receipts as well.

There is no sequencing defined for receipts. From UI we are following manual numbering/sequence for receipts, and we cannot see doc sequencing numbers for receipts in UI.

Can you please help us here to understand better.