threePlusOne.js

function threePlusOne(number) {
	console.info(number);
	if(number === 1 || number === 0) {
  	return number;
  } else {
  	if(number%2) {
    	threePlusOne(number * 3 + 1);
    } else {
    	threePlusOne(number / 2);
    }
  }
}

The Collatz Conjecture is the simplest math problem no one can solve — it is easy enough for almost anyone to understand but notoriously difficult to solve.