Private Sub Command1_Click() Dim a(100) As Boolean For i = 2 To 100 a(i) = True Next i For i = 2 To 10 If a(i) Then j = i + i Do While j <= 100 a(j) = False j = j + i Loop End If Next i k = 0 For i = 2 To 100 If a(i) Then For j = i To 100 If a(j) Then k = k + 1 Text1.Text = Text1.Text & i * j & " " If k Mod 5 = 0 Then Text1.Text = Text1.Text & vbCrLf End If Next j End If Next i End Sub