Two kings not in adjacent square How many ways are there to place two identical kings on an 8 x 8 chessboard so that the kings are not in adjacent squares? on an n x m chessboard?
Edit: I inserted the 'two' before 'identical'

placing the first king, we can place it in one of 3 'groups': in one of the corners, along the edge of the board but not in a corner, or not on an edge.
determine the number of places available for the other king in each of those 3 cases, and determine how many squares there are that satisfy each of the three cases.
