Hop til fane, navnet står i celle F1

Sub ValidateList_F1()
Dim ws As Worksheet
Dim validationString As String

For Each ws In Worksheets
    validationString = validationString & ws.Name & ", "
Next ws

    With Worksheets("Ark1").Range("F1").Validation
        .Delete
        .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _
        xlBetween, Formula1:=validationString
    End With
End Sub