we turn coffee into puzzles


SUMS Sudoku

The numbers 1--9 must each appear exactly once in each row, column, and block. In addition, all shaded regions of a given color add to the same sum; for example, if one red shaded region has entries that sum to 21, then all red shaded regions in that puzzle sum to 21. The sums are not given; you must determine them yourself.


Appeared in the conference program for the 2006 Shenandoah Undergraduate Mathematics and Statistics (SUMS) Conference at James Madison University, October 2006.