Data update

Task/M-bius-function/Swift/m-bius-function.swift

@@ -0,0 +1,36 @@
+import Foundation
+
+// Moebius function
+func mu(number: Int) -> Int {
+    var n = number
+    if n % 4 == 0 {
+        return 0
+    }
+    var primeFactors = 0
+    if n % 2 == 0 {
+        primeFactors += 1
+        n /= 2
+    }
+    var p = 3
+    while p * p <= n {
+        if n % p == 0 {
+            n /= p
+            if n % p == 0 {
+                return 0
+            }
+            primeFactors += 1
+        }
+        p += 2
+    }
+    if (n > 1) {
+        primeFactors += 1
+    }
+    return primeFactors % 2 == 0 ? 1 : -1
+}
+
+print("The first 199 Moebius numbers are:")
+print("   ", terminator: "")
+for i in 1..<200 {
+    print(String(format: "%3d", mu(number: i)),
+            terminator: (i + 1) % 20 == 0 ? "\n" : "")
+}