CS special topics courses have the following numbering system:


291A:  Applications, General
291D: Database and Information Systems 
291G: Security and Cryptography 
291H: Computational Science and Engineering 
291I: Visual Computing and Interaction
291K: Machine Learning and Data Mining           


292A: Algorithms
292C: Programming Languages and Software Eng.
292D: Foundations in Databases and Information Systems
292F: Foundations, General
292G: Security and Cryptography
292H: Computational Science and Engineering 


293B: Operating Systems and Distributed Systems
293C: Programming Languages and Software Eng.
293D: Database and Information Systems
293E: Computer Architecture and Embedded Systems
293G: Security and Cryptography
293K: Machine Learning and Data Mining        
293N: Networking
293S: Systems, General