Number systems August 26, 2008 Number systems PJ’s new ride Duino, Italy Posted on August 26, 2008 in Prehistory 0 Comments I wonder how you do a minus sign. Could do some cool number system -273 tshirts. Share this article: About ptsp 0 Comments Leave a reply Click here to cancel the reply Your email address will not be published. Required fields are marked *CommentName * Email * Website This site uses Akismet to reduce spam. Learn how your comment data is processed.