Tuesday, March 9, 2010
You Can Count on Monsters, by Richard Evan Schwartz
Schwartz is a mathematician and an artist, and his monsters are the numbers from 1 to 100. Number one is sad because it can't play the factoring game with the other numbers. He shows why, with factors trees that have 1's included, and can just go on forever. (His factor trees have the branches going up; mine have always gone down.)
The prime numbers are the basic monsters, and the other monsters are made from strange conglomorations of their prime factors. Searching for the factors in the composite monsters is sometimes easy (that's the 10 monster to the right) ...
Sometimes hard (that's 99 to the left)...
And always interesting.
My 7-year-old son was confused by 8. He thinks of 8 as four 2's, but there are only three 2's in the picture. I think it's a good confusion. My guess is that he'll eventually get how the composite monsters are made from other numbers, and then the 8 monster will suddenly feel right.
At the end, Schwartz gives lovely explanations of how to find the primes, and why they go on forever.
Available for $24.95 at AK Peters (the publisher); cheaper at Amazon (but check that shipping charge to make sure).
[Transparency: I got my copy of this book for free, as a review copy. But I think I might just buy 2 or 3 copies to give as presents. Yum!]