Denying repetitions of same random sequences

For example we have any number from 0 to 11, and I need to repeat the process a couple of times (my intention is too complicated to explain so just bear with me):

        Random ran = new Random();

        for (int i = 0; i < n; i++)
        {

            int n = ran.Next(0, 10);
            //......
        }

However, application mustn't ever repeat the same random sequence. How can i do this? I thought about forcingly excluding previous seeds each iteration, but i don't know how to manipulate seeds. Any idea? Also, first number choice MUST not be pseudo-random. Thanks in advance.