.NET Runescape Level to Experience Formula

'Written by Sixem
Public Function Experience(ByVal Level As Integer)
        Dim a As Long
        Dim x As Integer
        For x = 1 To Level - 1
            a = a + Int(x + 300 * (2 ^ (x / 7)))
        Next x
        Experience = (a / 4)
        Return Experience
    End Function