Програмирование в VBA выдает ошибку 5 и выделяет C = Atn(k / Sqr(1 - k * k)) ^ 2

Option Explicit
Sub laba2()
Dim k As Double, n As Double, J As Double, Ln As Double
Dim C As Double, D As Double, F As Double
Dim A As Double, y As Double, T As Double
k = InputBox("k="): n = InputBox("n=")
C = Atn(k / Sqr(1 - k * k)) ^ 2
D = Cos(k - 1)
J = Sqr(Abs(k ^ 2 + k ^ n))
Ln = Log(J)
A = Log(J) ^ 3
F = 3 ^ (k ^ 2 + 1)
T = -k ^ (n ^ 2)
y = C + D ^ 2 / A * J + F * Exp(T)
MsgBox ("y=" + Format(y, "fixed") + Chr(10) + "Syrskikh." + Chr(10) + " group KTM-12-2")
Debug.Print "y="; Format(y, "Fixed")
End Sub
Пишет ошибку 5 и выделяет C = Atn(k / Sqr(1 - k * k)) ^ 2

Спасибо помог!