Formula to merge like values in a column

Please see the attached excel file for an example of my situation.

In column A, One of three programs (101, 102, 103) is repeated for each country that participates in the program(column b). I'm hoping to find a formula that will merge all like values in column A, only showing the program number once for every country that participates in that program - the table to the right is how I would want it to appear.

I am desperate for a formula for this due to the fact that (1) my data set is so large and (2) When I merge them manually and try to filter by a program, only one of the associated countries shows up.

Any assistance would be greatly appreciated!