llFrand(), no repeats?

Hello, I am trying to create a script that uses llFrand(6) and will only output 4 random integers. I am able to output the random integers, but the problem is I get repeats . Here is part of my code:

while (x<4)
{
a = (integer)llFrand(6);
llOwnerSay((string)a);
x += 1;
}

My output is something like:
"3.000000"
"2.000000"
"3.000000"
"1.000000"

What do I do to get rid of these repeats?

You could make a list of the numbers, randomise it using llListRandomize, and then deal out the numbers from the list.

ETA:

list numbers = [0, 1, 2, 3, 4, 5];

default
{
    touch_start (integer count)
    {
        llOwnerSay (llList2CSV (llListRandomize (numbers, 1)));
    }
}

list numbers =[1, 2, 3, 4, 5, 6];//Dice?

default {
	touch_start(integer count) {
		list trimList = llList2List(llListRandomize(numbers, 1), 0, 3);
		llOwnerSay(llList2CSV(trimList));
	}
}

returns:
_temp1: 2, 1, 6, 5
_temp1: 2, 3, 6, 1
_temp1: 5, 1, 4, 6
_temp1: 3, 6, 2, 1
_temp1: 1, 2, 5, 3

PS

(integer)llFRand( 6.0 )

will yield 0-5,


(integer)llFRand( 6.0 ) + 1

will yield 1-6

llFRand generates numbers in a range of [0, x)

that means any fraction up to but not including the number you input, and since casting to integer removes the fractional part, you can never get an integer of your input size, unless you add 1 to it.

another way to look at it, is that your input number is the number of possible choices, and your addition will be the first number in that possible sequence