What is the difference between Invoice Reference Number and Invoice sequence number?

What is the difference between Invoice Reference Number and Invoice sequence number?

As clearly mentioned in the Annex 2 of E Invoicing Resolution, Invoice Reference Number (IRN): A unique, sequential note number, issued by taxpayer, as per Article 53(5)(b) of the VAT Implementing Regulation. This implies IRN is just another name for Invoice Sequence Number. Again, as specified in E Invoicing Resolution, the Compliant E-Invoice solution must have a tamper-resistant Electronic Invoice counter that cannot be reset or reformatted. The counter must increment for each generated Electronic Invoice or associated note and the Compliant Solution must record the value of this counter in each Electronic Invoice or associated Notes. Example 1,2,3,4,5…