关于RSA采用第三方公钥加密问题

这是一个MSDN上的一个实例，我简单改了一下，把明文固定了，但为什么每次加密的结果都不一致，是不是还有一个设置没有完成，请高手指点！！！using System;
using System.Security.Cryptography;
class Class1
{
   static void Main()
   {
      //initialze the byte arrays to the public key information.
      byte[] PublicKey = {214,46,220,83,160,73,40,39,201,155,19,202,3,11,191,178,56,
            74,90,36,248,103,18,144,170,163,145,87,54,61,34,220,222,
            207,137,149,173,14,92,120,206,222,158,28,40,24,30,16,175,
            108,128,35,230,118,40,121,113,125,216,130,11,24,90,48,194,
            240,105,44,76,34,57,249,228,125,80,38,9,136,29,117,207,139,
            168,181,85,137,126,10,126,242,120,247,121,8,100,12,201,171,
            38,226,193,180,190,117,177,87,143,242,213,11,44,180,113,93,
            106,99,179,68,175,211,164,116,64,148,226,254,172,147};
      byte[] Exponent = {1,0,1};
 
      byte[] EncryptedKey;
      byte[] MM = {1,2,3,4,5,6,7,8,9,0,1,2,3,4,5};      //Create a new instance of RSACryptoServiceProvider.
      RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();      //Create a new instance of RSAParameters.
      RSAParameters RSAKeyInfo = new RSAParameters();      //Set RSAKeyInfo to the public key values.
      RSAKeyInfo.Modulus = PublicKey;
      RSAKeyInfo.Exponent = Exponent;
      //Import key parameters into RSA.
      RSA.ImportParameters(RSAKeyInfo);      //Encrypt 
      EncryptedKey = RSA.Encrypt(MM, false);//EncryptedKey每次加密都不一致？？？
   }
}