IF OR different answers

Hi,

I thought the formula below would give me the result of:

7 if I5=1
6 if I5=2
5 if I5=3 and so on but it doesnt seem to work. Can anyone help with where I am going wrong?

=IF(OR(I5={1,2,3,4}),{7,6,5,4})

OR only returns a true or false value.
So if I5 is say 3, then it's
=IF(OR(I5={1,2,3,4}),{7,6,5,4})
=IF(TRUE,{7,6,5,4})

At this point, IF doesn't know what to do with the array of values, so it just picks the first value in the array.

Try this instead

=INDEX({7,6,5,4},MATCH(I5,{1,2,3,4},0))

try this one without or
=IF(I5=1,7,IF(I5=2,6,3))