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diff --git a/tests/src/JIT/Performance/CodeQuality/BenchmarksGame/fannkuch-redux/fannkuch-redux-serial.cs b/tests/src/JIT/Performance/CodeQuality/BenchmarksGame/fannkuch-redux/fannkuch-redux-serial.cs
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index 0000000000..646b68d2b4
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+++ b/tests/src/JIT/Performance/CodeQuality/BenchmarksGame/fannkuch-redux/fannkuch-redux-serial.cs
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+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+// Adapted from fannkuch-redux C# .NET Core #2 program
+// http://benchmarksgame.alioth.debian.org/u64q/program.php?test=fannkuchredux&lang=csharpcore&id=2
+// Best-scoring single-threaded C# .NET Core version as of 2017-09-01
+
+/* The Computer Language Benchmarks Game
+   http://benchmarksgame.alioth.debian.org/
+
+   contributed by Isaac Gouy, transliterated from Mike Pall's Lua program 
+*/
+
+using System;
+
+class FannkuchRedux
+{
+   public static int[] fannkuch(int n) {
+      int[] p = new int[n], q = new int[n], s = new int[n]; 
+      int sign = 1, maxflips = 0, sum = 0, m = n-1;
+      for(int i=0; i<n; i++){ p[i] = i; q[i] = i; s[i] = i; }      
+      do {
+         // Copy and flip.
+         var q0 = p[0];                                     // Cache 0th element.
+         if (q0 != 0){
+            for(int i=1; i<n; i++) q[i] = p[i];             // Work on a copy.
+            var flips = 1;
+            do { 
+               var qq = q[q0]; 
+               if (qq == 0){                                // ... until 0th element is 0.
+                  sum += sign*flips;
+	          if (flips > maxflips) maxflips = flips;   // New maximum?
+                  break; 
+               } 
+ 	       q[q0] = q0; 
+	       if (q0 >= 3){
+	          int i = 1, j = q0 - 1, t;
+                  do { t = q[i]; q[i] = q[j]; q[j] = t; i++; j--; } while (i < j); 
+               }
+	       q0 = qq; flips++;
+            } while (true); 
+         }
+         // Permute.
+         if (sign == 1){
+            var t = p[1]; p[1] = p[0]; p[0] = t; sign = -1; // Rotate 0<-1.
+         } else { 
+            var t = p[1]; p[1] = p[2]; p[2] = t; sign = 1;  // Rotate 0<-1 and 0<-1<-2.
+            for(int i=2; i<n; i++){ 
+	       var sx = s[i];
+	       if (sx != 0){ s[i] = sx-1; break; }
+	       if (i == m) return new int[]{sum,maxflips};  // Out of permutations.
+	       s[i] = i;
+	       // Rotate 0<-...<-i+1.
+	       t = p[0]; for(int j=0; j<=i; j++){ p[j] = p[j+1]; } p[i+1] = t;
+            }
+         }
+      } while (true);
+   }
+
+   static void Main(string[] args){
+      int n = (args.Length > 0) ? Int32.Parse(args[0]) : 7;
+      var pf = fannkuch(n);
+      Console.Write("{0}\nPfannkuchen({1}) = {2}\n", pf[0], n, pf[1]);
+   }
+}