Goal: write a loop that appends the sum of the last two items in [fib] to the end of [fib] for 20 loops and find the values of the last iteration.

Code Thus Far

let fib = [0,1]

let accumulator = 0

for (t=0;t<20;t++){
  endingDigits = fib[-1]+ fib[-2];
  accumulator =+ Number(accumulator) + Number(endingDigits);
  fib.push(endingDigits);
  t++;
}
console.log(fib)

Results I keep getting NaN - Which is why Rap the two negative indices in the number method.

Thanks for the help!