pascal

var f = function(n) {
  var f = 1; 
  for (var i = 1; i <= n; i ++) {
    f = f*i;
  }
  return f;
}


console.log(f(4))

var generate = function(numRows) {
    // numbers of rows create pascal tiangle 
    //pascal triangles that in each row both sides are the same 
    // generate n rows 
    //each row increase 1 by length
    //increase input until half and then decrease it 
  
    //create container array 
    //n!/(r!*(n-r)!) 
    var container = [];
    // for each n 
    for(var i = 1; i<= numRows; i++ ) {
      var row = new Array(i);
      
      for(var j = 0; j<row.length; j++) {
        row[j] = (f(i))/(f(j)*(f(i-j))); 
      }
      console.log(row);
      container.push(row);
    }
      //create a row array with i len
    
      
      
  
  
    //return container; 
    
};

console.log(generate(5));