Mozna zkus napsat, ceho chces docilit. Mozna by se naslo vhodnejsi reseni. Treba mne jeste napada
https://jsfiddle.net/qk2m3rsy/
<span id=aaa></span>
<script>
function writeText(str)
{
var el;
el = document.getElementById('aaa');
el.innerHTML = str;
}
writeText('1');
setTimeout("writeText('2')", 1000);
setTimeout("writeText('3')", 2000);
setTimeout("writeText('4')", 3000);
</script>