Add even Fibonacci numbers up to the Nth number provided. Because.

sumEvenFib.js

var sumEvenFib = function(number) {
  var _internalSumEvenFib = function(current, fib, num, sum) {
    return (num <= 1) ? sum : _internalSumEvenFib(fib, current + fib, --num, (!(fib % 2) ? sum + fib : sum));
  };
  return _internalSumEvenFib(1, 1, number, 0);
};