import rhinoscriptsyntax as rs

# delete everything and start from scratch
#allobj = rs.AllObjects()
#rs.DeleteObject(allobj)

bsize = 10         # side lenght of box
dist = 4           # distance between boxes
offs = bsize + dist# offset of boxes
num = 25           # number of boxes in one row

# create a box
corners = [(0,0,0), (bsize,0,0), (bsize,bsize,0), (0,bsize,0), 
          (0,0,bsize), (bsize,0,bsize), (bsize,bsize,bsize), (0,bsize,bsize)]

rs.EnableRedraw(False)

for i in range(num):
    for j in range(num):
        if ((i+j)%2) or ((i-j)%4) and ((i+j)%7) or ((i-j)%2):
            box = rs.AddBox(corners)
            rs.MoveObject(box, (i*offs,j*offs))

rs.EnableRedraw(True)