Lookup Nth occurrence in a row

[pillee]

Hi all,

I am trying to create a formula for a few days. It has been very hard for me.

What I want to do is to find a Nth value in a row. For example, there are invoice dates(always last date of the month) in one row and invoice numbers in another row. I would like to find the 3rd invoice number raised on 28 February.

I could find a lot of information about Nth occurrence in a column but not much in a row. It would be greatly appreciated if you could help me with this.

many thanks in advance,
Pil

[benishiryo]

welcome to the forum, Pil. you have all the same dates in row 4. i am assuming it is not that straightforward. if it is, then 3rd occurrence is simply:
=D5
or for you to key nth occurrence (say you key in A6):
=INDEX(5:5,A6+1)

but if dates are different, then perhaps this array formula (assuming 28Feb2018 keyed in A7):
=INDEX(B5:F5,SMALL(IF(B4:F4=A7,COLUMN(B5:F5)),3)-COLUMN(B5)+1)
...confirmed by pressing CTRL+SHIFT+ENTER to activate the array, not just ENTER. You will know the array is active when you see curly braces { } appear around your formula. If you do not CTRL+SHIFT+ENTER you will get an error or a clearly incorrect answer.

[pillee]

Thank you so much, benishiryo!!! Yes it is more complicated than the attached file but when I tried with your formula it worked perfectly. Awesome!!!!