Hello Lucio,

If you want your type of formula I suggest to take
=OFFSET($A$1,0,INT((COLUMN(B$1)-2)/4)*4+1)

But if you want to have a non-volatile function (that is: a function
which does not recalculate each and every time you press F9):
=INDEX($1:$1,0,FLOOR((COLUMN(B$1)-2),4)+2)

OFFSET is volatile, INDEX is not. BTW: FLOOR does exactly what you
introduce with INT(x/4)^4.

Regards,
Bernd