Guys please don't downvote my blog. I genuinely need the help. My doubt is if I am given a sequence 1,2,4,8,15,26,... Then how to find a closed formula for this series in this case. please help me. I know this is not relevant to cp. But it will genuinely help to understand the mathematical computation regarding solving subproblems.

As far as i have read this involves polynomial fitting. How to solve this by polynomial fitting . please kindly help.