In D2 enter:
=IF(ISNA(VLOOKUP(C2,$A$2:$A$100,1,0)),0,1)
Then copy down as required.
This will return 1 if the value is found in column A and 0 if it is not
found.

Hope this helps
Rowan

lvcha.gouqizi wrote:
Hi there,

I want to check a value to see if it is in an array. If it is in the
array then return true, else return false. I use LookUP function but it
does not work. Here is my table

A B C D
1 1 6 1
2 1 3 1
3 1 1 1

I want to check values in column C in Column A. If it is in {1,2,3}
then return 1 in Column D at the corresponding row. But the cell with 6
there also return 1. Any way to correct it?
Thanks.

lc