I tried this one but... it is not working and I don't know why
Code:
 mass {  
  var %i = $snick(#,0) 
  var %j = 0
  while (%j <= %i) {    
   .mode # -oooo $$snick(#,$calc(%j + 1)) $$snick(#,$calc(%j + 2)) $$snick(#,$calc(%j + 3)) $$snick(#,$calc(%j + 4))
    inc %j 4
  }
}