Internet and library resources

Regarding arithmetic progressions of prime number, please check Ivars Peterson's ``Math Trek'' article, ``Progressive Primes,'' at

http://www.maa.org/mathland/mathtrek_04_26_04.html

and the new article by Ben Green and Terence Tao: ``The primes contain arbitrarily long arithmetic progressions." Peterson's article includes a link to the Green - Tao paper.

Regarding the card game ``SET," consult the article ``The card game SET" by B. L. Davis and Diane Maclagan at

http://math.stanford.edu/126#75maclagan/papers/set.pdf and some of the references mentioned in that paper, especially

Roy Meshulam: ``On subsets of finite abelian groups with no 3-term arithmetic progressions," J. Comb. Theory-A 71 (1995), 168-172.