how many possible combinations are there for UOUOUOUOUO?

Question

I need to find out how many possible combinations there are for these 2 letters in a sequence of 10 digits. also is there some kind of generator i can use to produce all the combinations?

Answer 1

two ways for one letter, either U or O 2^1=2

for two letters there are 4 ways, if a letter is allowed to repeat, UU, OO, UO, OU 2^2=4

for three digits 2^3 = 8 ways

for 10 letters 2^10 = 1,024 combinations of two letters with 10 total letters