src/HOL/Library/Permutations.thy
changeset 33059 d1c9bf0f8ae8
parent 33057 764547b68538
child 33715 8cce3a34c122
equal deleted inserted replaced
33058:70f5c18e975d 33059:d1c9bf0f8ae8
    81 
    81 
    82 lemma permutes_univ: "p permutes UNIV \<longleftrightarrow> (\<forall>y. \<exists>!x. p x = y)"
    82 lemma permutes_univ: "p permutes UNIV \<longleftrightarrow> (\<forall>y. \<exists>!x. p x = y)"
    83   unfolding permutes_def by simp
    83   unfolding permutes_def by simp
    84 
    84 
    85 lemma permutes_inv_eq: "p permutes S ==> inv p y = x \<longleftrightarrow> p x = y"
    85 lemma permutes_inv_eq: "p permutes S ==> inv p y = x \<longleftrightarrow> p x = y"
    86   unfolding permutes_def inv_onto_def apply auto
    86   unfolding permutes_def inv_def apply auto
    87   apply (erule allE[where x=y])
    87   apply (erule allE[where x=y])
    88   apply (erule allE[where x=y])
    88   apply (erule allE[where x=y])
    89   apply (rule someI_ex) apply blast
    89   apply (rule someI_ex) apply blast
    90   apply (rule some1_equality)
    90   apply (rule some1_equality)
    91   apply blast
    91   apply blast