Blocks shall be constructed of responsibly forested wood. The size of each block shall be 3x7x2 centimeters.

The species of wood and design of a block would be dependent on characteristics of the number. For example, Mersenne primes may all be made from Bamboo, and Fibonacci primes may all be carved in a serif font.
-- ed, May 03 2009

Suitable for ages pi(x). Where pi(x) = x/ln x.
-- 4whom, May 03 2009


Or, suitable for ages totient (n) and cototient (n).
-- 4whom, May 03 2009


Suitable for those who's age can be divided by two...
-- 4whom, May 03 2009


I'll take the biggest one you got.
-- gnomethang, May 03 2009


Hang on, how big is it?
-- gnomethang, May 03 2009



random, halfbakery