I am a mathematician who left academia long ago after a Ph.d. from Caltech and a three year faculty appointment at the University of California, Santa Cruz. My research was related to the classification of finite simple groups. Many of the intervening years have been spent as a programmer and sometimes manager, including stints at HP Labs, two spin-offs of SRI, and a startup that merged with two other companies—the merged entity was acquired by Adobe.
A Public Service Announcement
Recurrences is a paper (or is it a book?) I have written on divide-and-conquer recurrences. There is also an application to difference equations. To the best of my knowledge, most of the material is unavailable elsewhere. Some of the content assumes access to Tom Leighton's Notes on Better Master Theorems for Divide-and-Conquer Recurrences, which contains errors discussed in my paper.