Goal:
  
  ============================
   (is_true
      (forallb (fun '(n, t) => n == find_index t)
         (combine (seq 0 (cardinality ())) (list_all ()))))


DEBUG:Going to execute:
vm_compute
Level 0: Backtrace:

Not enough uninstantiated existential variables.
Level 0: Backtrace:

Not enough uninstantiated existential variables.