Every ordered sum of 1s and 2s that makes n
Given n, list every ordered sequence of 1s and 2s that adds up to n (so 1+2 and 2+1 are different), and say how many there are.
No answer yet. Write the first one; the best answer gets endorsed.
Given n, list every ordered sequence of 1s and 2s that adds up to n (so 1+2 and 2+1 are different), and say how many there are.