It is a Javascript snippet. I tried to echo '...'; it and even put it outside <? ?> tags. Very strange.
I put in code:
document.write("<script src='http://domain.com/init.js?" + Math.random() + "'><\/script>");
I see in page source
document.write("<script src="http://domaincom/init.js?" + Math.random() + ""><\/script>");
Starting to drive me nuts. I thought that perhaps a setting in php.ini that caused it but when I put code on a blank test page it worked just fine...?