[1 3 5 7] x [1 3 5 7]

           25/16
            /|\
           / | \
          /35/32\
         /,'/|\`.\
       5/4-/-|-\15/8
       /|\/49/32\/ \
      / |/,'   `.\  \
     / 7/4------21/16\ 
    /,'   `.\ /,'   `.\
  1/1-------3/2-------9/8



  u[1 3 5 7] x u[1 3 5 7]

 16/9-------4/3-------1/1
    \`.   ,'/ \`.   ,'/
     \32/21/---\-8/7 /
      \ |\/.   ,\/| /
       \|/\64/49/\|/
      16/15------8/5
         \`.\|/,'/
          \64/35/
           \ | /
            \|/
           32/25



   [1 3 5 7] x u[1 3 5 7]
     (7-limit diamond)

       5/3-------5/4
       /|\`.   ,'/|\
      / | \10/7 / | \
     / 7/6-\/|\/-7/4 \
    /,'  \`/\|/\'/  `.\
  4/3-----/-1/1-\-----3/2
    \`.  /,'/|\`.\  ,'/
     \ 8/7------12/7 /
      \ | / 7/5 \ | /
       \|/,'   `.\|/
       8/5-------6/5