Koncept & J57 recently teamed up with Mike Maven (of Young Pandas) for this fantastic freestyle over Mos Def's classic "Mathematics" track, produced by the legendary DJ Premier. This freestyle is just the latest release in what promises to be an exciting future for Koncept & J57, the Brown Bag AllStars duo, who've been working together on a ton of new music. Maven, meanwhile, leaves his own mark on the record by lending his smooth vocals to the track. The "Mathematics" freestyle comes off DJ Caesar's upcoming mixtape Reliving the 90's: Part 2. (DJ Caesar is a member of DJ Whoo Kid's The Terminators crew, as well as a DJ on SHADE45). Stream and download the "Mathematics" freestyle below, and let us know what you think.