INDEX(array,row,col,area)
array: cell or inline array
row: desired row, defaults to 1
col: desired column, defaults to 1
area: from which area to select a cell, defaults to 1
INDEX gives a reference to a cell in the given array. The cell is selected by row and col, which count the rows and columns in the array.
If the reference falls outside the range of array, INDEX returns #REF!