const fibonacciSum=(n)=>{ let prev=0; let current=1; let sum=1; let total=1; for(let i=1; i<n; i++){ sum=prev+current total+=sum prev=current current=sum // console.log('Previous: ', prev) // console.log('Current: ', current) } return total } console.log(fibonacciSum(6)) console.log(fibonacciSum(5))