Can someone help with the logic for a coin change problem?

Question

Given a Sum of S . Should be changed to a sequence of 1's and 2's where no 2's should come together in a single sequence. We need to find the count of max possible such sequences for given sum.

Example : S=3
{1,1,1}
{1,2}
{2,1}
Max possible sequence count will be 3

Answer 1

Can I see your attempt? It'll help me point out your errors instead of giving you the answer key