Initial data commit

Task/Totient-function/VBA/totient-function.vba

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+Private Function totient(ByVal n As Long) As Long
+    Dim tot As Long: tot = n
+    Dim i As Long: i = 2
+    Do While i * i <= n
+        If n Mod i = 0 Then
+            Do While True
+                n = n \ i
+                If n Mod i <> 0 Then Exit Do
+            Loop
+            tot = tot - tot \ i
+        End If
+        i = i + IIf(i = 2, 1, 2)
+    Loop
+    If n > 1 Then
+        tot = tot - tot \ n
+    End If
+    totient = tot
+End Function
+
+Public Sub main()
+    Debug.Print " n  phi   prime"
+    Debug.Print " --------------"
+    Dim count As Long
+    Dim tot As Integer, n As Long
+    For n = 1 To 25
+        tot = totient(n)
+        prime = (n - 1 = tot)
+        count = count - prime
+        Debug.Print Format(n, "@@"); Format(tot, "@@@@@"); Format(prime, "@@@@@@@@")
+    Next n
+    Debug.Print
+    Debug.Print "Number of primes up to 25     = "; Format(count, "@@@@")
+    For n = 26 To 100000
+        count = count - (totient(n) = n - 1)
+        Select Case n
+            Case 100, 1000, 10000, 100000
+                Debug.Print "Number of primes up to"; n; String$(6 - Len(CStr(n)), " "); "="; Format(count, "@@@@@")
+            Case Else
+        End Select
+    Next n
+End Sub