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Proof step 1 from proof hpal-next (conclusion) (back to tree)

finout(g) ⊦ ∀ x. x ≠ [] ∧ pathp(g)(⌜x⌝ ) ∧ haspathanylength(g)(x.last) → (∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last))

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: finout-def: ⊦ finout(g) ↔ (∀ a. ∃ s. ∀ b. edge(g)(a, b) ↔ b ∈ s);

Proof step 2 from proof hpal-next (previous step) (back to tree)

x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), ∀ a. ∃ s. ∀ b. edge(g)(a, b) ↔ b ∈ s ⊦ ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

User applied rule all left

And obtained the following new goals

Rule argument

pos: left 4 terms: x.last abort: F discard: T computed: T

Additional information

Used terms: x.last

Proof step 3 from proof hpal-next (previous step) (back to tree)

x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), ∃ s. ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 4 from proof hpal-next (previous step) (back to tree)

x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

User applied rule cut formula

And obtained the following new goals

Rule argument

fma: ∀ a. a ∈ s → ¬ haspathanylength(g)(a)

Additional information

Used formulas: ∀ a. a ∈ s → ¬ haspathanylength(g)(a)

Proof step 5 from proof hpal-next (previous step) (back to tree)

x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ a. a ∈ s → ¬ haspathanylength(g)(a) ⊦ ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

User applied rule apply lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name:hpal-next-aux, seq:∀ b. edge(g)(a, b) ↔ b ∈ s, ∀ b. b ∈ s → ¬ haspathanylength(g)(b) ⊦ ¬ haspathanylength(g)(a), subst:[g, a, s] → [g, x.last, s]

Additional information

Used terms: g, x.last, s

Proof step 6 from proof hpal-next (previous step) (back to tree)

∀ b. edge(g)(a, b) ↔ b ∈ s, ∀ b. b ∈ s → ¬ haspathanylength(g)(b) ⊦ ¬ haspathanylength(g)(a)

Lemma hpal-next-aux

Proof step 7 from proof hpal-next (previous step) (back to tree)

x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), ∀ a. a ∈ s → ¬ haspathanylength(g)(a), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ ∀ b. b ∈ s → ¬ haspathanylength(g)(b), ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: size-zero-01: ⊦ s ≠ ∅ → # s ≠ 0; (forward) from specification set-basic ne-01: ⊦ a ∈ s → s ≠ ∅; (forward) from specification set-basic

Proof step 8 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(b), pathp(g)(⌜x⌝ ), b ∈ s, ∀ a. a ∈ s → ¬ haspathanylength(g)(a), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

Heuristic quantifier closing applied rule all left

And closed the goal!

Rule argument

pos: left 8 terms: b

Additional information

Used terms: b

Proof step 9 from proof hpal-next (previous step) (back to tree)

x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ ∀ a. a ∈ s → ¬ haspathanylength(g)(a), ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: size-zero-01: ⊦ s ≠ ∅ → # s ≠ 0; (forward) from specification set-basic ne-01: ⊦ a ∈ s → s ≠ ∅; (forward) from specification set-basic

Proof step 10 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(a), pathp(g)(⌜x⌝ ), a ∈ s, ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ ∃ y. (∃ b. y = x + b ') ∧ pathp(g)(⌜y⌝ ) ∧ haspathanylength(g)(y.last)

User applied rule exists right

And obtained the following new goals

Rule argument

pos: right 1 terms: x + a ' abort: F discard: T computed: F

Additional information

Used terms: x + a '

Proof step 11 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(a), haspathanylength(g)(x.last), pathp(g)(⌜x⌝ ), a ∈ s, ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦ (∃ b. x + a ' = x + b ') ∧ pathp(g)(⌜x + a '⌝ ) ∧ haspathanylength(g)((x + a ').last)

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ (x + a ').last = a; (s) ⊦ ⌜x + y⌝ = ⌜x⌝ + ⌜y⌝ ; (s) ⊦ a ' = a0 ' ↔ a = a0; (s) ⊦ # x = # z → (x + y = z + y0 ↔ x = z ∧ y = y0); (ws)

Proof step 12 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(a), pathp(g)(⌜x⌝ ), a ∈ s, ¬ pathp(g)(⌜x⌝ + ⌜a '⌝ ), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: infgraph-gen, name: pathp-def, seq:⊦ pathp(g)(σ) ↔ (∀ n. ⌜n⌝ < # σ → dom(g)(σ[n])) ∧ (∀ n. ⌜n + 1⌝ < # σ → edge(g)(σ[n], σ[n + 1])), subst:[σ, g] → [⌜x⌝ , g], <all paths>

Additional information

Used terms: ⌜x⌝ , g

Proof step 13 from proof hpal-next (previous step) (back to tree)

⊦ pathp(g)(σ) ↔ (∀ n. ⌜n⌝ < # σ → dom(g)(σ[n])) ∧ (∀ n. ⌜n + 1⌝ < # σ → edge(g)(σ[n], σ[n + 1]))

A spec-lemma

Proof step 14 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, ¬ pathp(g)(⌜x⌝ + ⌜a '⌝ ), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. ⌜n⌝ < # ⌜x⌝ → dom(g)(⌜x⌝ [n]), ∀ n. ⌜n + 1⌝ < # ⌜x⌝ → edge(g)(⌜x⌝ [n], ⌜x⌝ [n + 1]) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ ⌜x⌝ [n] = x[n]; (s) ⊦ ⌜m⌝ < ⌜n⌝ ↔ m < n; (s) ⊦ # ⌜x⌝ = ⌜# x⌝ ; (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 ⊦ ⌜n⌝ + ⌜m⌝ < ⌜n0⌝ ↔ n + m < n0; (s) c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ ⌜m + n⌝ = ⌜m⌝ + ⌜n⌝ ; (s)

Proof step 15 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, ¬ pathp(g)(⌜x⌝ + ⌜a '⌝ ), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ n. n < # x → dom(g)(x[n]) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: infgraph-gen, name: pathp-def, seq:⊦ pathp(g)(σ) ↔ (∀ n. ⌜n⌝ < # σ → dom(g)(σ[n])) ∧ (∀ n. ⌜n + 1⌝ < # σ → edge(g)(σ[n], σ[n + 1])), subst:[σ, g] → [⌜x⌝ + ⌜a '⌝ , g], <all paths>

Additional information

Used terms: ⌜x⌝ + ⌜a '⌝ , g

Proof step 16 from proof hpal-next (previous step) (back to tree)

⊦ pathp(g)(σ) ↔ (∀ n. ⌜n⌝ < # σ → dom(g)(σ[n])) ∧ (∀ n. ⌜n + 1⌝ < # σ → edge(g)(σ[n], σ[n + 1]))

A spec-lemma

Proof step 17 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, ∀ n. n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, (∃ n. ¬(⌜n⌝ < #(⌜x⌝ + ⌜a '⌝ ) → dom(g)((⌜x⌝ + ⌜a '⌝ )[n]))) ∨ (∃ n. ¬(⌜n + 1⌝ < #(⌜x⌝ + ⌜a '⌝ ) → edge(g)((⌜x⌝ + ⌜a '⌝ )[n], (⌜x⌝ + ⌜a '⌝ )[n + 1]))) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: append-assoc: ⊦ (σ + σ1) + σ2 = σ + σ1 + σ2; from specification stream ⊦ (⌜x⌝ + ⌜x0⌝ )[m] = (x + x0)[m]; (s) a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ n < # x → (x + a ')[n] = x[n]; (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 ⊦ ⌜m⌝ < ⌜n⌝ ↔ m < n; (s) ⊦ n∞ + ⌜0⌝ = n∞; (s) ⊦ m ≤ n → (⌜(* m)⌝ + n∞2 < ⌜(* n)⌝ + n∞1 ↔ n∞2 < ⌜n - m⌝ + n∞1); (s) ⊦ # a ' = 0 +1; (s) ⊦ # ⌜x⌝ = ⌜# x⌝ ; (s) ⊦ #(σ + σ1) = # σ + # σ1; (s) c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ ⌜m + n⌝ = ⌜m⌝ + ⌜n⌝ ; (s) ⊦ ⌜n⌝ < ⌜1⌝ + n∞ ↔ ¬ n∞ < ⌜n⌝ ; (s)

Proof step 18 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ n. n < # x → dom(g)(x[n]), ¬(¬ # x < n → dom(g)((x + a ')[n])) ∨ ¬(n0 < # x → edge(g)(x[n0], (x + a ')[n0 + 1])) ⊦

User applied rule case distinction

And obtained the following new goals

Rule argument

pos: left 10

Additional information

Proof step 19 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, ¬ # x < n, ¬ dom(g)((x + a ')[n]), ∀ n. n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

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 20 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ n. n < # x → dom(g)(x[n]) ⊦

User applied rule all left

And obtained the following new goals

Rule argument

pos: left 11 terms: n abort: F discard: T computed: F

Additional information

Used terms: n

Proof step 21 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: <toplevel>, name: haspathanylength-def, seq: ⊦ haspathanylength(g)(a) ↔ (∀ n. ∃ x. x.head = a ∧ # x = n + 1 ∧ pathp(g)(⌜x⌝ )), subst:[a, g] → [a, g], <all paths>

Additional information

Used terms: a, g

Proof step 22 from proof hpal-next (previous step) (back to tree)

⊦ haspathanylength(g)(a) ↔ (∀ n. ∃ x. x.head = a ∧ # x = n + 1 ∧ pathp(g)(⌜x⌝ ))

Lemma haspathanylength-def

Proof step 23 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), n < # x → dom(g)(x[n]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ n. ∃ x. x.head = a ∧ # x = n + 1 ∧ pathp(g)(⌜x⌝ ) ⊦

User applied rule all left

And obtained the following new goals

Rule argument

pos: left 11 terms: 0 abort: F discard: T computed: F

Additional information

Used terms: 0

Proof step 24 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∃ x. x.head = a ∧ # x = 0 + 1 ∧ pathp(g)(⌜x⌝ ) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ x + [] = x; (s) ⊦ a + x = a ' + x; (s) ⊦ # x = 1 ↔ x = x.head + []; (as) c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic

Proof step 25 from proof hpal-next (previous step) (back to tree)

x0 = x0.head ', # s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x0⌝ ), x0.head ∈ s, n ≤ # x, ¬ dom(g)((x + x0)[n]), n < # x → dom(g)(x[n]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]) ⊦

Heuristic elimination applied rule apply elim lemma

And obtained the following new goals

Rule argument

spec: list-data, name:elim-list-c, seq:x ≠ [] ⊦ a = x.head ∧ y = x.tail ↔ x = a + y, subst:[x, a, y] → [x0, a, x1]

Additional information

Used simplifier rules: ⊦ a ' ≠ []; (s) x ≠ [] ⊦ a = x.head ∧ y = x.tail ↔ x = a + y; (elim) Used terms: x0, a, x1

Proof step 26 from proof hpal-next (previous step) (back to tree)

x0 = a ', x0 = a + x1, # s ≠ 0, s ≠ ∅, x ≠ [], x0 ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x0⌝ ), a ∈ s, n ≤ # x, ¬ dom(g)((x + x0)[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

User applied rule all left

And obtained the following new goals

Rule argument

pos: left 14 terms: a abort: F discard: T computed: T

Additional information

Used terms: a

Proof step 27 from proof hpal-next (previous step) (back to tree)

edge(g)(x.last, a) ↔ a ∈ s, x0 = a + x1, x0 = a ', # s ≠ 0, s ≠ ∅, x ≠ [], x0 ≠ [], haspathanylength(g)(x.last), pathp(g)(⌜x0⌝ ), a ∈ s, n ≤ # x, ¬ dom(g)((x + x0)[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ a ' ≠ []; (s) a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ a ' = a0 ' + x ↔ a = a0 ∧ x = []; (ws) ⊦ a + x = a ' + x; (s)

Proof step 28 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], edge(g)(x.last, a), haspathanylength(g)(x.last), pathp(g)(⌜a '⌝ ), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: infgraph-gen, name: pathp-def, seq:⊦ pathp(g)(σ) ↔ (∀ n. ⌜n⌝ < # σ → dom(g)(σ[n])) ∧ (∀ n. ⌜n + 1⌝ < # σ → edge(g)(σ[n], σ[n + 1])), subst:[g, σ] → [g, ⌜a '⌝ ], <all paths>

Additional information

Used terms: g, ⌜a '⌝

Proof step 29 from proof hpal-next (previous step) (back to tree)

⊦ pathp(g)(σ) ↔ (∀ n. ⌜n⌝ < # σ → dom(g)(σ[n])) ∧ (∀ n. ⌜n + 1⌝ < # σ → edge(g)(σ[n], σ[n + 1]))

A spec-lemma

Proof step 30 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], edge(g)(x.last, a), haspathanylength(g)(x.last), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ n. ⌜n⌝ < # ⌜a '⌝ → dom(g)(⌜a '⌝ [n]), ∀ n. ⌜n + 1⌝ < # ⌜a '⌝ → edge(g)(⌜a '⌝ [n], ⌜a '⌝ [n + 1]) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ a '[0] = a; (s) ⊦ ⌜x⌝ [n] = x[n]; (s) ⊦ m < 1 ↔ m = 0; (s) ⊦ ⌜m⌝ < ⌜n⌝ ↔ m < n; (s) ⊦ # a ' = 0 +1; (s) ⊦ # ⌜x⌝ = ⌜# x⌝ ; (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 ⊦ ¬ n < 0; (s) ⊦ m ≤ n → (⌜(* m)⌝ + n∞2 < ⌜(* n)⌝ ↔ n∞2 < ⌜n - m⌝ ); (s) c: ⊦ m + n = n + m; from specification nat-basic a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic ⊦ ⌜m + n⌝ = ⌜m⌝ + ⌜n⌝ ; (s)

Proof step 31 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], dom(g)(a), edge(g)(x.last, a), haspathanylength(g)(x.last), a ∈ s, n ≤ # x, ¬ dom(g)((x + a ')[n]), n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: list-del, name: get-append-grt, seq: ⊦ ¬ n < # x → (x + y)[n] = y[n - # x], subst:[x, y, n] → [x, a ', n], <all paths>

Additional information

Used simplifier rules: ⊦ m < n ↔ ¬ n ≤ m; (ss) ⊦ m ≤ n → (n ≤ m ↔ m = n); (s) ⊦ m ≤ m; (s) ⊦ m - m = 0; (s) ⊦ a '[0] = a; (s) ⊦ m < n → m ≤ n; (s) ⊦ n < # x → (x + a ')[n] = x[n]; (s) a: ⊦ (x + y) + z = x + y + z; from specification list Used terms: x, a ', n

Proof step 32 from proof hpal-next (previous step) (back to tree)

⊦ ¬ n < # x → (x + y)[n] = y[n - # x]

A spec-lemma

Proof step 33 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], n0 < # x, haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, ¬ edge(g)(x[n0], (x + a ')[n0 + 1]), ∀ n. n < # x → dom(g)(x[n]), ∀ n. n + 1 < # x → edge(g)(x[n], x[n + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

User applied rule all left

And obtained the following new goals

Rule argument

pos: left 10 terms: n0 abort: F discard: T computed: F

Additional information

Used terms: n0

Proof step 34 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], n0 < # x, haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, ¬ edge(g)(x[n0], (x + a ')[n0 + 1]), n0 + 1 < # x → edge(g)(x[n0], x[n0 + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n < # x → dom(g)(x[n]) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Used simplifier rules: ⊦ # x = 0 ↔ x = []; (s) f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic

Proof step 35 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], n0 < # x, haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, ¬ edge(g)(x[n0], (x + a ')[n0 + 1]), n0 + 1 < # x → edge(g)(x[n0], x[n0 + 1]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s, ∀ n. n < # x → dom(g)(x[n]) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: list-del, name: get-append-less, seq: ⊦ n < # x → (x + y)[n] = x[n], subst:[x, y, n] → [x, a ', n0 + 1], <all paths>

Additional information

Used terms: x, a ', n0 + 1

Proof step 36 from proof hpal-next (previous step) (back to tree)

⊦ n < # x → (x + y)[n] = x[n]

A spec-lemma

Proof step 37 from proof hpal-next (previous step) (back to tree)

# s ≠ 0, s ≠ ∅, x ≠ [], n0 < # x, haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, ¬ n0 + 1 < # x, ¬ edge(g)(x[n0], (x + a ')[n0 + 1]), n0 + 1 < # x → edge(g)(x[n0], x[n0 + 1]), ∀ n. n < # x → dom(g)(x[n]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

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 ⊦ ¬ n < n; (s) ⊦ m < n + 1 ↔ ¬ n < m; (s) ⊦ m + n < m + n0 ↔ n < n0; (s) ⊦ m < n → (n ≤ m + 1 ↔ n = m + 1); (s) ⊦ m + 1 ≠ 0; (s) lf-01: ⊦ m < n ∧ n = n0 → m < n0; (forward) from specification nat-basic f: ⊦ m < n → n ≠ 0; (forward) from specification nat-basic eqle-one: ⊦ m = n + 1 ∧ n < n0 → m ≤ n0; (forward) from specification nat a: ⊦ (x + y) + z = x + y + z; from specification list ⊦ n = # x → (x + a ')[n] = a; (s) ⊦ m < n ↔ ¬ n ≤ m; (ss)

Proof step 38 from proof hpal-next (previous step) (back to tree)

# x = n0 + 1, # s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, ¬ edge(g)(x[n0], a), ∀ n. ¬ n0 < n → dom(g)(x[n]), ∀ b. edge(g)(x.last, b) ↔ b ∈ s ⊦

User applied rule all left

And obtained the following new goals

Rule argument

pos: left 10 terms: a abort: F discard: T computed: T

Additional information

Used terms: a

Proof step 39 from proof hpal-next (previous step) (back to tree)

# x = n0 + 1, edge(g)(x.last, a) ↔ a ∈ s, # s ≠ 0, s ≠ ∅, x ≠ [], haspathanylength(g)(a), haspathanylength(g)(x.last), a ∈ s, ¬ edge(g)(x[n0], a), ∀ n. ¬ n0 < n → dom(g)(x[n]) ⊦

Heuristic simplifier applied rule simplifier

And obtained the following new goals

Rule argument

Additional information

Proof step 40 from proof hpal-next (previous step) (back to tree)

# x = n0 + 1, # s ≠ 0, s ≠ ∅, x ≠ [], edge(g)(x.last, a), haspathanylength(g)(x.last), haspathanylength(g)(a), a ∈ s, ¬ edge(g)(x[n0], a), ∀ n. ¬ n0 < n → dom(g)(x[n]) ⊦

User applied rule apply rewrite lemma

And obtained the following new goals

Rule argument

spec: list-del, name: get-last-nonempty, seq: ⊦ n = # x - 1 ∧ 0 < # x → x[n] = x.last, subst:[x, n] → [x, n0], <all paths>

Additional information

Used simplifier rules: ⊦ 0 < m ↔ m ≠ 0; (s) ⊦ # x = 0 ↔ x = []; (s) ⊦ n ≤ m → m + n0 - n = (m - n) + n0; (s) ⊦ n + 0 = n; (s) a: ⊦ (m + n0) + n1 = m + n0 + n1; from specification nat-basic c: ⊦ m + n = n + m; from specification nat-basic Used terms: x, n0

Proof step 41 from proof hpal-next (previous step) (back to tree)

⊦ n = # x - 1 ∧ 0 < # x → x[n] = x.last

A spec-lemma

Proof Tree for hpal-next (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