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Staircase climbs using jumps of two or more

Question

A rabbit stands at the bottom of a 1010-step staircase. Every hop moves it up by at least 22 steps (any number of steps that is 22 or more). How many different sequences of hops take it exactly to the top of step 1010?

Short answer

3434. Count compositions of 10 into parts of size at least 2. If hnh_n is the count for nn steps, removing the last stair from a final hop of size at least 3, or deleting a final hop of size exactly 2, gives hn=hn−1+hn−2h_n=h_{n-1}+h_{n-2} with h0=1,h1=0h_0=1,h_1=0. That is a Fibonacci sequence and h10=34h_{10}=34.

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