set(arithmetic).

list(distinct).
  [r2,r3,r4,r5,r6,r11].
end_of_list.

formulas(cabby).
  number != 0.
  number  = 2  * r2  + 1.
  number  = 3  * r3  + 1.
  number  = 4  * r4  + 1.
  number  = 5  * r5  + 1.
  number  = 6  * r6  + 1.
  number  = 11 * r11.
end_of_list.

