Global Instance valid_rnd_NA : Valid_rnd (Znearest (Zle_bool 0)) := valid_rnd_N _.

Theorem generic_inclusion_ln_beta : forall x, ( x <> R0 -> (fexp2 (ln_beta beta x) <= fexp1 (ln_beta beta x))%Z ) -> generic_format fexp1 x -> generic_format fexp2 x.