Replicate Array without Duplicates

Hi All,

Column A has a number of values descending vertically e.g. 1, 1, 2, 3, 4, 4, 5 etc. For example, let's say A2:A30

In column D I want a formula that I can drag down, that replicates the only the original data in this array e.g. 1, 2, 3, 4, 5.

My array changes month to month which is the reason I'm looking for a quick fire solution to this, as oppose copy, paste and remove duplicates.

Thanks

Hi Stuart

You could try this in D2 and drag down

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until it gets to 0 then #N/A which means no more data in column A.