Comment Some simple explanations on complex topics (Score 1) 517
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Understanding the FFT, Second Edition
http://www.amazon.com/Understanding-Second-Revised-Anders-Zonst/dp/0964568152/
Examples are in BASIC (with line numbers even), but very simple explaination of the fast Fourier transform.
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Adventures in Group Theory: Rubik's Cube, Merlin's Machine, and Other Mathematical Toys (2nd edition)
http://www.amazon.com/Adventures-Group-Theory-Merlins-Mathematical/dp/0801890136/
Introduction to group theory using Rubik's cubes. Lots of typos, but they won't slow you down much.
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Cryptography Decrypted
http://www.amazon.com/Cryptography-Decrypted-H-X-Mel/dp/0201616475/
Cryptography explained in pictures.
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