<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<script>
function boom()
{
var mss = document.getElementById("mss");
var j = document.createTextNode("j");
var comb = document.createTextNode("\u0302");
mss.appendChild(j);
mss.appendChild(comb);
}
</script>
</head>
<body onload="boom()">
<div>
<math xmlns="http://www.w3.org/1998/Math/MathML" display="block">
<msub id="mss">
<mi>v</mi>
<mn>1</mn>
</msub>
</math>
</div>
</body>
</html>