Prerequisites for

In Code: A Mathematical Journey
Flannery, Sarah / Flannery, David. 2000, UK 1st edition. 271 pages.
Note: I have not read the newer US 1st edition (release date 2001).
Categories: Biographical
This book is the story of how Sarah Flannery captured the headlines with her Cayley-Purser encryption algorithm. I was privileged to briefly talk with Ron Rivest about her as these events were unfolding. He had recently talked with her on the phone, and spoke well of her. Having success so early has probably put a lot of pressure on Ms. Flannery to continue to do "genius" things, so it seems that she's avoiding the lime light, at least until her education is completed.
While the UK version of her book doesn't discuss her algorithm in detail (apparently the more recent US version does, and has over 100 more pages), she gives an account of the events that made the world stop and look -- all with a refreshing humility that is rare among cryptographers. Much of the book provides an enjoyable introduction to modular arithmetic. The book requires little mathematical background, but a curiosity for things mathematical is a must.

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