I need a formula that can read vertically down the contents of a column of
data and list all of the results in another column. I do not want to list
duplicate results, I only want the first instance listed once, then ignore
any exact matches that have already been identified after that.

EXAMPLE:

Column A, Column B (column "B" would be the results of reading
column "A")
1 1
3 3
87 87
3 60
60 5
3 4
5 9
87
60
4
9
1
5
5
5
1
4
9
9
1

The results in column "B" would be similar to the display you see when
clicking the down arrow on a column of data when the sort is enabled.

Can someone help me please.
Thank you, David D.