CRC Standard Mathematical Tables and Formula -- Even when I was eight years old, I had a fascination with this book. And even today, I don't understand everything inside it. This book is a must-have for anyone serious about recreational mathematics.
The Master Crossword Puzzle Dictionary by Herbert M. Baus -- For solving word puzzle, or as a thesaurus, this book is unmatched.
The 15 books of Mathematical Recreations by Martin Gardner -- These were the inspiration for my degree in math, and for this site. They are excellent reading material, and many are available in libraries.
Many different books by Clifford Pickover, especially Computers, Pattern, Chaos, and Beauty .... Mazes for the Mind .... and Computers and the Imagination. Check out his web site for a taste.
Winning Ways by Berlekamp, Conway, and Guy. The definitive book for Game Theory. This set of two books is hard to obtain and expensive, but you can order it through your library.
New Rules for Classic Games by R. Wayne Schmittberger. For a taste the variety of games described in this book, use this link.
Numerical Recipes in C by Press, Teukolsky, Vettering, and Flannery. A fantastic book packed with programs for mathematical argorithms. The website contains the entire book. This book showed me wavelets and the traveling salesman problem.
The Encyclopedia of Integer Sequences by N J A Sloane and Simon
Plouffe. This book will answer any question of the type "what is
next in this sequence?" Example:
M5368 1, 102, 162, 274, 300, 412, 562, 592, 728, 1084, 1094, 1108, 1120, 1558, 1566, 1630, 1804, 1876, 2094, 2162, 2164, 2238, 2336, 2388, 2420, 2494, 2524, 2614.
n^64 + 1 is prime. Ref rgw. [1,2; A6316]
A list of number lists can be kinda dry, but it's a great reference. To test a sequence, write to
firstname.lastname@example.org containing 1 line like
lookup 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Start at the beginning, give lots of terms. Minus signs are OK. The program will try VERY hard to find an
The Art of Computer Programming by Donald
E. Knuth. A classic work, with revised editions in 1998.
Volume 2 has an excellent study on Prime Factorizations, among other things.