Boucle selon une condition

Function D(A As Long, B As Long, C As Long) As Long
    Coef = 1
    If C < A Then
        Do While D < A
            Temp = C + (Coef * B)
            D = Temp
            If Temp > A Then Exit Function
            Coef = Coef + 1
        Loop
    End If
End Function

    Range("D2:D" & [C10000].End(xlUp).Row).FormulaR1C1 = "=D(R2C1,R2C2,RC[-1])"

Function D(A As Long, B As Long, C As Long) As Long
    D = C + B
    If D >= A Then
        D = 0
        Exit Function
    End If
    Coef = 1
    If C < A Then
        Do While D < A
            Temp = C + (Coef * B)
            If Temp < A Then
                D = Temp
                Coef = Coef + 1
            Else
                Exit Function
            End If
        Loop
    End If
End Function