proposition: Theorem In10' : In 10 [1;2;3;4;5;6;7;8;9;10].
proof: Proof. repeat (left; reflexivity). repeat (right; try (left; reflexivity)). Qed.
imports: Coq.Bool.Bool Coq.Arith.Arith Coq.Arith.EqNat Coq.omega.Omega Coq.Lists.List Coq.omega.Omega Maps