import rhinoscriptsyntax as rs
import random as ran

allobjs = rs.AllObjects()
rs.DeleteObjects(allobjs)

bsize = 5               # seitenlaenge der box
dist = 20               # abstand zwischen boxen
offs = bsize + dist     # offset der boxen
num = 21                # anzahl der boxen in einer reihe

# erstelle eine 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) % 20) and ((i-j) % 20):
                box = rs.AddBox(corners)
                rs.MoveObject(box, (i*offs,j*offs,50))


rs.EnableRedraw(True)