数式：\text{this is a pen}


            <a href="http://exp.frozenlib.net/query?exp=%5ctext%7bthis+is+a+pen%7d"><img src="http://exp.frozenlib.net/image?exp=%5ctext%7bthis+is+a+pen%7d&amp;size=7&amp;textcolor=000000FF&amp;backcolor=FFFFFFFF" alt="\text{this is a pen}" style="border:none;" /></a>

$\text{this is a pen}$

画像貼り付け用HTML