Hi there, I need a bit of a hand writing a formula.

I have a column of numbers that has duplicates and triplicates in it; I'm
trying to concatenate the data conditionally - something like this:

if(a2=a3), concatenate(c2:c3, d2:d3 ...) then select and delete row a3.
It then needs to apply the same formula, repeating the same process, or
stepping down a row if a2<a3...

Any help appreciated.

Cheers