I'm weaving a scarf. I have 2 threads for the weft and each one can be either black or white. Each is on it's own shuttle. I want to use them in combinations of 1-5 threads in a single repeat of any order. How many different orders can I have? For example: DDLLL for the first order for 10 throws of the shuttle, DDDLL for the 2nd order for 10 throws of the shuttle, DLLLL for the 3rd order for 20 throws of the shuttle, DLDL, DLD, LDL, DL, LD, etc.
I can't quite figure out which is "n" and which is "r" and if there is a third parameter I am not accounting for. I have never studied combinatorics.