Hey all, I'm here in Nova Scotia at a conference, and I was speaking with a professor and work she's doing. She's working on so called "multidigit representations". The basic gist is this: Let B = NxN dilation matrix (matrix with positive eigenvalues) of integers. Let D be a set of N dimensional row vectors (a particular set). Then for v1, ..., vk in D, SUM(i = 0 to k) B^i v_i is a multidigit number, which should remind you of our single dimensional system. The set D can be derived from finding the lattice points in the square {(x,y) | -1/2 < x,y <= 1/2} transformed by B. So D is the set of coset representatives Z^n/B(Z^n). An interesting choice of B is the twin dragon matrix [[1,1],[-1,1]] and the digit set {[0,0], [-1,1]}. Note that the number of digits equals the determinant of B. This base and digit set will constitute all points in Z^2. Anyone have any comments or fun things you can do with this? There are sums and matrices involved, I know one of you will get hooked. Sincerely, Robert