src/HOL/SMT/Examples/cert/z3_linarith_09

simple tests

(benchmark Isabelle
:extrafuns (
  (uf_1 Int)
  (uf_2 Int)
 )
:assumption (<= 3 uf_1)
:assumption (= uf_2 (+ uf_1 4))
:assumption (not (< 0 (- uf_2 uf_1)))
:formula true
)