Inline single-use modulo helpers

PerfectNumbers.Core/ULongExtensions.cs

@@ -221,8 +221,7 @@ public static class ULongExtensions
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static ulong Mod6(this ulong value)
         {
-                ulong key = (value.Mod3() << 1) | (value & 1UL);
-                return Mod6Lookup[(int)key];
+                return Mod6Lookup[(int)(((value.Mod3() << 1) | (value & 1UL)))];
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
@@ -647,4 +646,4 @@ public static class ULongExtensions
 
 		return false;
 	}
-}
+}