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Proof step 1 from proof inv-inverts-last (conclusion) (back to tree)

⊦ stutf(nσ) ∧ # nσ = ⌜n⌝ + ⌜1⌝ → inv(nσ)[nσ[n]] = n

System applied rule normalize

And obtained the following new goals

Rule argument

Additional information

Proof step 2 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , inv(nσ)[nσ[n]] ≠ n, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 3 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , inv(nσ)[nσ[n]] ≠ n, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:inv-def, seq:⊦ stutf(nσ) → inv(nσ) = (leninv(nσ) = ∞ ⊃ ⌜λ m. max∞(λ n. ⌜n⌝ < # nσ ∧ nσ[n] = m).n⌝ ;⌜λ m. max∞(λ n. ⌜n⌝ < # nσ ∧ nσ[n] = m).n⌝ to leninv(nσ).n ), subst:[nσ] → [nσ], <all paths>

Additional information

Used terms: nσ

Proof step 4 from proof inv-inverts-last (previous step) (back to tree)

⊦ stutf(nσ) → inv(nσ) = (leninv(nσ) = ∞ ⊃ ⌜λ m. max∞(λ n. ⌜n⌝ < # nσ ∧ nσ[n] = m).n⌝ ;⌜λ m. max∞(λ n. ⌜n⌝ < # nσ ∧ nσ[n] = m).n⌝ to leninv(nσ).n)

Lemma inv-def

Proof step 5 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , (leninv(nσ) = ∞ ⊃ ⌜λ m. max∞(λ n. ⌜n⌝ < # nσ ∧ nσ[n] = m).n⌝ ;⌜λ m. max∞(λ n. ⌜n⌝ < # nσ ∧ nσ[n] = m).n⌝ to leninv(nσ).n)[nσ[n]] ≠ n, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜nf⌝ to n = ⌜nf to n⌝ ; (s) c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ n∞ = ⌜m⌝ + ⌜n0⌝ → (⌜n⌝ < n∞ ↔ n < m + n0); (s) add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf

Proof step 6 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , (leninv(nσ) = ∞ ⊃ ⌜λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n⌝ ;⌜(λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to leninv(nσ).n⌝ )[nσ[n]] ≠ n, stutf(nσ) ⊦

User applied rule case distinction

And obtained the following new goals

Rule argument

pos: left 2

Additional information

Proof step 7 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, ⌜λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n⌝ [nσ[n]] ≠ n, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜nf⌝ [n] = nf(n); (s)

Proof step 8 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, stutf(nσ) ⊦

User applied rule cut formula

And obtained the following new goals

Rule argument

fma: max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) = ∞

Additional information

Used formulas: max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) = ∞

Proof step 9 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ n∞ = ⌜m⌝ + ⌜n0⌝ → (⌜n⌝ < n∞ ↔ n < m + n0); (s) add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf

Proof step 10 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) = ∞, ∞.n ≠ n, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:maxinf-inf, seq: ⊦ max∞(np) = ∞ ↔ (∀ n. ∃ n0. n < n0 ∧ np(n0)) ∨ (∀ n. ¬ np(n)), subst:[np] → [λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]], <all paths>

Additional information

Used terms: λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]

Proof step 11 from proof inv-inverts-last (previous step) (back to tree)

⊦ max∞(np) = ∞ ↔ (∀ n. ∃ n0. n < n0 ∧ np(n0)) ∨ (∀ n. ¬ np(n))

Lemma maxinf-inf

Proof step 12 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, ∞.n ≠ n, stutf(nσ), (∀ n0. ∃ n1. n0 < n1 ∧ ¬ n < n1 ∧ nσ[n1] = nσ[n]) ∨ (∀ n0. ¬(¬ n < n0 ∧ nσ[n0] = nσ[n])) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 13 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, ∞.n ≠ n, stutf(nσ), (∀ n0. ∃ n1. n0 < n1 ∧ ¬ n < n1 ∧ nσ[n1] = nσ[n]) ∨ (∀ n0. n < n0 ∨ nσ[n0] ≠ nσ[n]) ⊦

User applied rule case distinction

And obtained the following new goals

Rule argument

pos: left 5

Additional information

Proof step 14 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, ∞.n ≠ n, stutf(nσ), ∀ n0. ∃ n1. n0 < n1 ∧ ¬ n < n1 ∧ nσ[n1] = nσ[n] ⊦

User applied rule all left

And closed the goal!

Rule argument

pos: left 5 terms: n abort: F discard: F computed: F

Additional information

Used terms: n

Proof step 15 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, ∞.n ≠ n, stutf(nσ), ∀ n0. n < n0 ∨ nσ[n0] ≠ nσ[n] ⊦

Heuristic quantifier closing applied rule all left

And closed the goal!

Rule argument

pos: left 5 terms: n

Additional information

Used simplifier rules: ⊦ ¬ n < n; (s) Used terms: n

Proof step 16 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) ≠ ∞, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ n∞ = ⌜m⌝ + ⌜n0⌝ → (⌜n⌝ < n∞ ↔ n < m + n0); (s) add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf

Proof step 17 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) ≠ ∞, stutf(nσ) ⊦

Heuristic elimination applied rule apply elim lemma

And obtained the following new goals

Rule argument

spec: nat-inf, name:elim, seq: ⊦ n∞ ≠ ∞ → (n = n∞.n ↔ n∞ = ⌜n⌝ ), subst:[n∞, n] → [max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]), n1]

Additional information

Used simplifier rules: ⊦ n∞ ≠ ∞ → (n = n∞.n ↔ n∞ = ⌜n⌝ ); (elim) Used terms: max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]), n1

Proof step 18 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) ≠ ∞, n1 ≠ n, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜n⌝ ≠ ∞; (s)

Proof step 19 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) = ⌜n1⌝ , n1 ≠ n, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:maxinf-fin, seq: ⊦ max∞(np) = ⌜n⌝ ↔ np(n) ∧ (∀ m. np(m) → ¬ n < m), subst:[n, np] → [n1, λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]], <all paths>

Additional information

Used terms: n1, λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]

Proof step 20 from proof inv-inverts-last (previous step) (back to tree)

⊦ max∞(np) = ⌜n⌝ ↔ np(n) ∧ (∀ m. np(m) → ¬ n < m)

Lemma maxinf-fin

Proof step 21 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , nσ[n1] = nσ[n], leninv(nσ) = ∞, n1 ≠ n, stutf(nσ), ¬ n < n1, ∀ m. ¬ n < m ∧ nσ[m] = nσ[n] → ¬ n1 < m ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ m < n → n ≠ 0; (s) f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic ⊦ m ≠ n → (m < n ↔ ¬ n < m); (ss)

Proof step 22 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , nσ[n1] = nσ[n], leninv(nσ) = ∞, n1 ≠ n, n1 < n, stutf(nσ), ∀ m. ¬ n < m ∧ nσ[m] = nσ[n] → ¬ n1 < m ⊦

User applied rule all left

And closed the goal!

Rule argument

pos: left 7 terms: n abort: F discard: F computed: T

Additional information

Used simplifier rules: ⊦ ¬ n < n; (s) Used terms: n

Proof step 23 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , ⌜(λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to leninv(nσ).n⌝ [nσ[n]] ≠ n, leninv(nσ) ≠ ∞, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜x⌝ [n] = x[n]; (s)

Proof step 24 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , ((λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to leninv(nσ).n)[nσ[n]] ≠ n, leninv(nσ) ≠ ∞, stutf(nσ) ⊦

Heuristic elimination applied rule apply elim lemma

And obtained the following new goals

Rule argument

spec: nat-inf, name:elim, seq: ⊦ n∞ ≠ ∞ → (n = n∞.n ↔ n∞ = ⌜n⌝ ), subst:[n∞, n] → [leninv(nσ), n1]

Additional information

Used simplifier rules: ⊦ n∞ ≠ ∞ → (n = n∞.n ↔ n∞ = ⌜n⌝ ); (elim) Used terms: leninv(nσ), n1

Proof step 25 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ((λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to n1)[nσ[n]] ≠ n, leninv(nσ) ≠ ∞, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜n⌝ ≠ ∞; (s)

Proof step 26 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ((λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to n1)[nσ[n]] ≠ n, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: stream[natstream], name:get-infto, seq:m < n ⊦ (nf to n)[m] = nf(m), subst:[m, n, nf] → [nσ[n], n1, λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n], <all paths>

Additional information

Used terms: nσ[n], n1, λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n

Proof step 27 from proof inv-inverts-last (previous step) (back to tree)

m < n ⊦ (nf to n)[m] = nf(m)

A spec-lemma

Proof step 28 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ((λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to n1)[nσ[n]] ≠ n, stutf(nσ), ¬ nσ[n] < n1 ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ m < n ↔ ¬ n ≤ m; (ss)

Proof step 29 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ((λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to n1)[nσ[n]] ≠ n, stutf(nσ), n1 ≤ nσ[n] ⊦

User applied rule constructor cut

And obtained the following new goals

Rule argument

var: n1

Additional information

Used simplifier rules: leninv-invlast: ⊦ # nσ = ⌜m⌝ + ⌜1⌝ ∧ leninv(nσ) = ⌜n⌝ + ⌜1⌝ ∧ stutf(nσ) → nσ[m] = n; nat freely generated by 0, +1;; ⊦ ⌜m + n⌝ = ⌜m⌝ + ⌜n⌝ ; (s) add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ ¬ n < n; (s) m < n ⊦ (nf to n)[m] = nf(m); (s) ⊦ m +1 = m + 1; (s) ⊦ m + m0 ≤ m ↔ m0 = 0; (s) a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic c: ⊦ m + n = n + m; from specification nat-basic

Proof step 30 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , n1 = 0, ((λ m. max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = m).n) to n1)[nσ[n]] ≠ n, stutf(nσ), n1 ≤ nσ[n] ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ 0 ≤ m; (s) ⊦ nf to 0 = []; (s)

Proof step 31 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜0⌝ , [][nσ[n]] ≠ n, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:leninv-zero, seq: ⊦ stutf(nσ) → (leninv(nσ) = ⌜0⌝ ↔ nσ = ⌜λ n. 0⌝ ), subst:[nσ] → [nσ], <all paths>

Additional information

Used simplifier rules: ⊦ # ⌜nf⌝ = ∞; (s) ⊦ ⌜m⌝ + n∞ = ∞ ↔ n∞ = ∞; (s) ⊦ ⌜n⌝ ≠ ∞; (s) add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf Used terms: nσ

Proof step 32 from proof inv-inverts-last (previous step) (back to tree)

⊦ stutf(nσ) → (leninv(nσ) = ⌜0⌝ ↔ nσ = ⌜λ n. 0⌝ )

Lemma leninv-zero

Proof step 33 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, nσ[n] < n1, stutf(nσ) ⊦

User applied rule cut formula

And obtained the following new goals

Rule argument

fma: max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) = ∞

Additional information

Used formulas: max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) = ∞

Proof step 34 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) = ∞, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, nσ[n] < n1, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ m < n → n ≠ 0; (s) f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ n∞ = ⌜m⌝ + ⌜n0⌝ → (⌜n⌝ < n∞ ↔ n < m + n0); (s) add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf

Proof step 35 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) = ∞, ∞.n ≠ n, nσ[n] < n1, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:maxinf-inf, seq: ⊦ max∞(np) = ∞ ↔ (∀ n. ∃ n0. n < n0 ∧ np(n0)) ∨ (∀ n. ¬ np(n)), subst:[np] → [λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]], <all paths>

Additional information

Used terms: λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]

Proof step 36 from proof inv-inverts-last (previous step) (back to tree)

⊦ max∞(np) = ∞ ↔ (∀ n. ∃ n0. n < n0 ∧ np(n0)) ∨ (∀ n. ¬ np(n))

Lemma maxinf-inf

Proof step 37 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ∞.n ≠ n, nσ[n] < n1, stutf(nσ), (∀ n0. ∃ n1. n0 < n1 ∧ ¬ n < n1 ∧ nσ[n1] = nσ[n]) ∨ (∀ n0. ¬(¬ n < n0 ∧ nσ[n0] = nσ[n])) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 38 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ∞.n ≠ n, nσ[n] < n1, stutf(nσ), (∀ n0. ∃ n1. n0 < n1 ∧ ¬ n < n1 ∧ nσ[n1] = nσ[n]) ∨ (∀ n0. n < n0 ∨ nσ[n0] ≠ nσ[n]) ⊦

User applied rule case distinction

And obtained the following new goals

Rule argument

pos: left 6

Additional information

Proof step 39 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ∞.n ≠ n, nσ[n] < n1, stutf(nσ), ∀ n0. ∃ n1. n0 < n1 ∧ ¬ n < n1 ∧ nσ[n1] = nσ[n] ⊦

User applied rule all left

And closed the goal!

Rule argument

pos: left 6 terms: n abort: F discard: F computed: F

Additional information

Used terms: n

Proof step 40 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , ∞.n ≠ n, nσ[n] < n1, stutf(nσ), ∀ n0. n < n0 ∨ nσ[n0] ≠ nσ[n] ⊦

Heuristic quantifier closing applied rule all left

And closed the goal!

Rule argument

pos: left 6 terms: n

Additional information

Used simplifier rules: ⊦ ¬ n < n; (s) Used terms: n

Proof step 41 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, max∞(λ n0. ⌜n0⌝ < # nσ ∧ nσ[n0] = nσ[n]) ≠ ∞, nσ[n] < n1, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ m < n → n ≠ 0; (s) f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ n∞ = ⌜m⌝ + ⌜n0⌝ → (⌜n⌝ < n∞ ↔ n < m + n0); (s) add-comm: ⊦ n∞1 + n∞2 = n∞2 + n∞1; from specification nat-inf add-assoc: ⊦ (n∞ + n∞1) + n∞2 = n∞ + n∞1 + n∞2; from specification nat-inf

Proof step 42 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]).n ≠ n, max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) ≠ ∞, nσ[n] < n1, stutf(nσ) ⊦

Heuristic elimination applied rule apply elim lemma

And obtained the following new goals

Rule argument

spec: nat-inf, name:elim, seq: ⊦ n∞ ≠ ∞ → (n = n∞.n ↔ n∞ = ⌜n⌝ ), subst:[n∞, n] → [max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]), n2]

Additional information

Used simplifier rules: ⊦ n∞ ≠ ∞ → (n = n∞.n ↔ n∞ = ⌜n⌝ ); (elim) Used terms: max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]), n2

Proof step 43 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) = ⌜n2⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) ≠ ∞, n2 ≠ n, nσ[n] < n1, stutf(nσ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜n⌝ ≠ ∞; (s)

Proof step 44 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , leninv(nσ) = ⌜n1⌝ , max∞(λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]) = ⌜n2⌝ , n2 ≠ n, nσ[n] < n1, stutf(nσ) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:maxinf-fin, seq: ⊦ max∞(np) = ⌜n⌝ ↔ np(n) ∧ (∀ m. np(m) → ¬ n < m), subst:[n, np] → [n2, λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]], <all paths>

Additional information

Used terms: n2, λ n0. ¬ n < n0 ∧ nσ[n0] = nσ[n]

Proof step 45 from proof inv-inverts-last (previous step) (back to tree)

⊦ max∞(np) = ⌜n⌝ ↔ np(n) ∧ (∀ m. np(m) → ¬ n < m)

Lemma maxinf-fin

Proof step 46 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , nσ[n2] = nσ[n], leninv(nσ) = ⌜n1⌝ , n2 ≠ n, nσ[n] < n1, stutf(nσ), ¬ n < n2, ∀ m. ¬ n < m ∧ nσ[m] = nσ[n] → ¬ n2 < m ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ m < n → n ≠ 0; (s) f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic ⊦ m ≠ n → (m < n ↔ ¬ n < m); (ss)

Proof step 47 from proof inv-inverts-last (previous step) (back to tree)

# nσ = ⌜n⌝ + ⌜1⌝ , nσ[n2] = nσ[n], leninv(nσ) = ⌜n1⌝ , n2 ≠ n, n2 < n, nσ[n] < n1, stutf(nσ), ∀ m. ¬ n < m ∧ nσ[m] = nσ[n] → ¬ n2 < m ⊦

User applied rule all left

And closed the goal!

Rule argument

pos: left 8 terms: n abort: F discard: F computed: T

Additional information

Used simplifier rules: ⊦ ¬ n < n; (s) Used terms: n

Proof Tree for inv-inverts-last (View conclusion)

The following image shows the proof tree of sequent calculus. The proved goal is at the bottom. You can click on the nodes to view additional rules. See here for details on colors in a proof tree.

the proof tree