Look up Fibonacci numbers F1,$1,$ F2,$2,$ F3...$3...$ if you are not familiar with them. Recall that Fi +$+$Fi+1=$+1=$ Fi+2.$+2.$

The first few Fibonacci numbers are 1,1,2,3,5,8,...$1,1,2,3,5,8,...$

Find the largest constant C such that Fn =$=$ O($($Cn).$).$