Exclude null contents into Request

I'm trying to do a table where there's a checkbox and a quantity count (if checked), and null contents are being sent. Is there a way to exclude that?

For reference:

<td>
    <label class="checkbox deliveryNotesLabel">
    <input type="checkbox" class="deliveryNotes" name="deliveryNotes[]" value="{{ $item->id }}"/>
        <span></span>
    </label>
</td>
<td>
    <input type="number" min="0" max="100" name="vans[]" class="form-control">
</td>

this is what $request->all() retrieves when I try to pick 2nd and 3rd items:

array:3 [▼
  "_token" => "DzGh2Q7fjhfbr4iexJ1c4AaTd8QlrA60zBphMgV7"
  "vans" => array:4 [▼
    0 => null
    1 => "1"
    2 => "2"
    3 => null
  ]
  "deliveryNotes" => array:2 [▼
    0 => "8"
    1 => "7"
  ]
]