June 2018 Update

Task/Fibonacci-n-step-number-sequences/VBA/fibonacci-n-step-number-sequences.vba

@@ -0,0 +1,62 @@
+Option Explicit
+
+Sub Main()
+Dim temp$, T() As Long, i&
+    'Fibonacci:
+    T = Fibonacci_Step(1, 15, 1)
+    For i = LBound(T) To UBound(T)
+        temp = temp & ", " & T(i)
+    Next
+    Debug.Print "Fibonacci: " & Mid(temp, 3)
+    temp = ""
+
+    'Tribonacci:
+    T = Fibonacci_Step(1, 15, 2)
+    For i = LBound(T) To UBound(T)
+        temp = temp & ", " & T(i)
+    Next
+    Debug.Print "Tribonacci: " & Mid(temp, 3)
+    temp = ""
+
+    'Tetranacci:
+    T = Fibonacci_Step(1, 15, 3)
+    For i = LBound(T) To UBound(T)
+        temp = temp & ", " & T(i)
+    Next
+    Debug.Print "Tetranacci: " & Mid(temp, 3)
+    temp = ""
+
+    'Lucas:
+    T = Fibonacci_Step(1, 15, 1, 2)
+    For i = LBound(T) To UBound(T)
+        temp = temp & ", " & T(i)
+    Next
+    Debug.Print "Lucas: " & Mid(temp, 3)
+    temp = ""
+End Sub
+
+Private Function Fibonacci_Step(First As Long, Count As Long, S As Long, Optional Second As Long) As Long()
+Dim T() As Long, R() As Long, i As Long, Su As Long, C As Long
+
+    If Second <> 0 Then S = 1
+    ReDim T(1 - S To Count)
+    For i = LBound(T) To 0
+        T(i) = 0
+    Next i
+    T(1) = IIf(Second <> 0, Second, 1)
+    T(2) = 1
+    For i = 3 To Count
+        Su = 0
+        C = S + 1
+        Do While C >= 0
+            Su = Su + T(i - C)
+            C = C - 1
+        Loop
+        T(i) = Su
+    Next
+    ReDim R(1 To Count)
+    For i = 1 To Count
+        R(i) = T(i)
+    Next
+    Fibonacci_Step = R
+End Function