A simple implementation of fibonacci in javascript.

fibonacci.js

function fibonacci(size) {

  var first = 0, 
      second = 1, 
      next, 
      count = 2, 
      result = [first, second];

  if(size < 2) {
    console.log(result);
    return;
  }


  while(count++ < size) {
    next = first + second;
    first = second;
    second = next;
    result.push(next);
  }
  
  console.log(result);
} 
 
fibonacci(5);