n=input() x,y=n/2,0 a=[n*['']for _ in[0]*n] for c in range(1,n*n+1): \x09a[y][x]="%3d"%c \x09u,v=(x+1)%n,(y+2)%n \x09if a[v][u]:u,v=x,(y+1)%n \x09x,y=u,v\x09 for r in a:print' '.join(r)
Note that non-ascii characters in the above source code will be escaped (such as \x9f).