せかいのー

PHP 
<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8">
<title>なつかしの</title>

<style>

.three{
	color:#F00;
	font-weight:bold;
	font-size:1.2em;
}
.five{
	color:#FF0;
	font-weight:bold;
	font-size:1.2em;
}
.fifteen{
	color:#00F;
	font-weight:bold;
	font-size:1.6em;
}
.other{

}

table{
border-collapse:collapse;
}

th{
  border:1px solid #666;
	width:100px;
}

td{
  border:1px solid #666;
	width:100px;
}
</style>

<!--[if lte IE 9]>
<script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
<![endif]-->
<!--[if lte IE 9]>
<script src="http://ie7-js.googlecode.com/svn/version/2.1(beta4)/IE9.js"></script>
<![endif]-->
</head>
<body>
<table><tr>
	<?php
	
	$max=100;
	
	for($i=0;$i<$max;$i++){
		
		$viewer=$i+1;
		
		$mod3 = $viewer%3;
		$mod5 = $viewer%5;
		$mod15 = $viewer%15;

		if($mod15==0){
			print("<td class=\"fifteen\">{$viewer}</td></tr>".closeTag($viewer));
		}else if($mod5==0){
			print("<td class=\"five\">{$viewer}</td></tr>".closeTag($viewer));
		}else if($mod3==0){
			print("<td class=\"three\">{$viewer}</td>");
		}else{
			print("<td class=\"other\">{$viewer}</td>");
		}
	}
	

	function closeTag($index){
		$rtn;
		if($index!=100){
			$rtn="</tr>";
		}
		return $rtn;
	}

	?>
</table>
  
</body>
</html>

まあ、実行してみてください。