Something like this formula

```
=OFFSET($A$3,,ROW()-ROW($A$3))
```

in `A4:A9`

?

**Edit**

In this formula, `ROW($A$3)`

is the row number of the cell `A3`

,
that is, just a number `3`

.
Dollar prefixes in front of `A`

and `3`

means that this is an absolute
reference, and it will stay the same when copied to another cell(s).
Just `ROW()`

means the row number of the cell, where the formula is,
so it would mean `4`

for the cell `A4`

, `5`

for the cell `A5`

and so on.
The combination `ROW()-ROW($A$3)`

is a standard way to have a consequent numbers
in a column of cells, so in the example,
for the cell `A4`

, expression

```
ROW()-ROW($A$3)
```

means

```
4 - 3 = 1,
```

for `A5`

- `=2`

, and so on.

The whole formula

```
=OFFSET($A$3,,ROW()-ROW($A$3))
```

for every cell can be translated as follows:
add `ROW()-ROW($A$3)`

numbers of **columns**
to the column number, where `$A$3`

is (which is 1,
since `A`

is the first column), and copy the content of the cell found
to the cell, where the formula is.

For more details and examples on functions `OFFSET`

and `ROW`

,
check out the `Excel`

help section `Lookup & Reference`

functions.