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    • Std/lists
    • Remove-duplicates

    Std/lists/remove-duplicates-equal

    Lemmas about remove-duplicates-equal available in the std/lists library.

    Definitions and Theorems

    Theorem: remove-duplicates-equal-when-atom

    (defthm remove-duplicates-equal-when-atom
            (implies (atom x)
                     (equal (remove-duplicates-equal x)
                            nil)))

    Theorem: remove-duplicates-equal-of-cons

    (defthm remove-duplicates-equal-of-cons
            (equal (remove-duplicates-equal (cons a x))
                   (if (member a x)
                       (remove-duplicates-equal x)
                       (cons a (remove-duplicates-equal x)))))

    Theorem: consp-of-remove-duplicates-equal

    (defthm consp-of-remove-duplicates-equal
            (equal (consp (remove-duplicates-equal x))
                   (consp x)))

    Theorem: len-of-remove-duplicates-equal

    (defthm len-of-remove-duplicates-equal
            (<= (len (remove-duplicates-equal x))
                (len x))
            :rule-classes ((:rewrite) (:linear)))

    Theorem: remove-duplicates-equal-of-list-fix

    (defthm remove-duplicates-equal-of-list-fix
            (equal (remove-duplicates-equal (list-fix x))
                   (remove-duplicates-equal x)))

    Theorem: list-equiv-implies-equal-remove-duplicates-equal-1

    (defthm list-equiv-implies-equal-remove-duplicates-equal-1
            (implies (list-equiv x x-equiv)
                     (equal (remove-duplicates-equal x)
                            (remove-duplicates-equal x-equiv)))
            :rule-classes (:congruence))

    Theorem: set-equiv-implies-set-equiv-remove-duplicates-equal-1

    (defthm set-equiv-implies-set-equiv-remove-duplicates-equal-1
            (implies (set-equiv x x-equiv)
                     (set-equiv (remove-duplicates-equal x)
                                (remove-duplicates-equal x-equiv)))
            :rule-classes (:congruence))

    Theorem: no-duplicatesp-equal-of-remove-duplicates-equal

    (defthm no-duplicatesp-equal-of-remove-duplicates-equal
            (no-duplicatesp-equal (remove-duplicates-equal x)))

    Theorem: duplicity-in-of-remove-duplicates-equal

    (defthm duplicity-in-of-remove-duplicates-equal
            (equal (duplicity a (remove-duplicates-equal x))
                   (if (member a x) 1 0)))

    Theorem: remove-duplicates-equal-of-remove

    (defthm remove-duplicates-equal-of-remove
            (equal (remove-duplicates-equal (remove a x))
                   (remove a (remove-duplicates-equal x))))