Hi all,
I need your help again!

I have two worksheets.

worksheet one is the source
Worksheet two will contain the formula

worksheet one:

1 black a b c
2 green b a d
3 white c a b g
4 white d
5 white e h i
6 white f
7 blue g c a
8 yellow h
9 red i a b c



Worksheet two:

1 black a b c
2 green b a d
4 white c a b g d e h i f
7 blue g c a
8 yellow h
9 red i a b c


The formula i am looking for will be on the columns where the letters
are.
This will probably be some sort of look up formula, the results of
which will list all the letters based on the colors despite that the
numbers and order will differ.

Thanks!