Logistic function

function logistic_chaos(r,x,n){
  if (isNaN(r) || r <0 || r > 4){
    throw "logistic_chaos: r has to be a number in between 0 and 4 (inclusive)! r="+r;
  }else if(isNaN(r) || x <0 || x > 1 ){
    throw "logistic_chaos: x0 has to be a number in between 0 and 4 (inclusive)! r="+r;
  }else if(isNaN(n) || n < 0) {
    for(let i = 0; i < n; i++){
      let newF = r*x*(1-x);
      document.writeln(newF+"<br>");
      x = newF;
    }
  }
}

logistic_chaos(2, 0.3, 10);