var arr = [1,3,4,5,6,7,4,3,2,4,5,6,7,3,2];

function find(){

var newArr = [];

for (var i = 0; i < arr.length; i++) {

if (newArr.indexOf(arr[i]) == -1 ) {

newArr.push(arr[i]);

}

}

document.write(newArr);

}

find(arr);