I've written a snippet to find all the possible combinations of a given system. I wrote it so I could test out the Wolfram automata system with more than two colours. I needed a way to figure out what combinations I would need to apply rules for growth.

I figured out that the standard black and white rules were simply the progression of the binary number system. Therefore: I simply need to model a number system of a given base and a number of digits.

It works but I'm wondering if I could have done it simpler - I tend to miss these things and do it the hard way:
Code:

int digits = 3; // the amount of slots
int base = 3; // the quantity of numbers per slot
int [][] combo;
void setup(){
  combo = combinations(digits, base);
  for(int i = 0; i < combo.length; i++){
    for(int j = 0; j < combo[i].length; j++)
	print(combo[i][j]+":");
    print("\n");
  }
  println("combinations:"+combo.length);
}
int [][] combinations(int digits, int base){
  //returns all possible combinations
  //format: [combination index][digit]
  int [] digit = new int[digits];
  for(int i = 0; i < digit.length; i++)
    digit[i] = 0;
  combo = new int[int(pow(base, digits))][digits];
  for(int i = 0; i < combo.length; i++){
    for(int j = 0; j < combo[i].length; j++){
	combo[i][j] = digit[j];
    }
    digit[digit.length-1]++;
    for(int k = digit.length-1; k > 0; k--)
	if(digit[k] >= base){
	  digit[k] = 0;
	  digit[k-1]++;
	}
  }
  return combo;
}