I didn't know either, but I thought that my friend, who is the Moderator of the MENSA Classical Music Special Interest Group might. Here is his response:"Oh oh oh! Mr. Kotter! Mr. Kotter! I know that tune! Everything I know about music, I learned from PDQ Bach. His chamber piece The Musical Sacrifice is based on this very tune: "Da kommt ja der Schurke" ["Here Comes the Villain"] That's how I finally learned its name. However I don't know how "Here Comes the Villain" originated. Possibly it might came from a popular song or a vamp in vaudeville or 19th-Century melodramas, similar to "Shave and a Haircut"."That's all I can tell you.