for i:=1 to 20 do
     for j:=1 to i do
       for k:=1 to j do
         if (i-j)(i-k)(j-k) \not equal to 0, then
           print i * j + k

for i:=1 to 20 do
    for j:=1 to i do
      for k:=1 to j do
        if (i-j)(j-k) \not equal to 0, then
          print i * j + k

for i:=1 to 20 do
          for j:=i+1 to 21 do
            for k:=j+1 to 22 do
               print i * j + k