Is there a function conditionally to concatenate cells and delete certain rows?

Question

I have an Excel sheet with data arranged like this:

For every row of column A that repeats (by necessity as the database is arranged alphabetically) I need to concatenate the number for the repeating row from column B into the cell above it (inserting, say, a comma between the two strings). Then I need to delete the repeating row to end up with the following:

Breaking this down:

1. In column A, identify a row that is a copy of the row above it.
2. Concatenate the information from column B of the repeated row into the original row, column B.
3. Delete the repeated row.
4. Repeat until a blank cell is encountered.

I hope someone will advise me on the possibility of producing a function that would execute these actions. I'm looking for a push in the right direction or confirmation that it isn't possible, rather than someone to solve the issue for me.

Answer 1

No, formulae do not delete rows.