I would prefer the following steps:
1. fill a blank column with numbers 1 to 1000
2. Apply vlookup in an adjacent column using the existing data as table range.
3. Now filter the column with vlookup formula for #N/A to identify missing numbers in existing data.
I guess the details of receipt no. are in separate columns currently. If so, first use a if+concatenate functions first, to get the receipt no. in a single cell. Then apply vlookup wherever necessary.
The if+concatenate function would be like...