← Session 21 — Tier ii′ planning + launch: close SfBoundProp in Lean (D-064)
thinking (10567 chars)
Progress — hre1 is now proved. Remaining:
1. hfre (line 158-160): after `rw [hf, hS, hd, Complex.add_re, hre1]` — the goal:
`↑n * z.re / ‖z‖ ^ 2 + ((S - ↑n) / z).re = ↑n * z.re / ‖z‖ ^ 2 + ((↑n + (S - ↑n) - ↑n) / z).re`
The LHS is the goal's RHS from hfre's statement; the RHS has `((↑n + (S − ↑n) − ↑n)/z).re` — because hd rewrote (1/z)*(n + (S−n)) = n*(1/z) + (S−n)/z — WAIT no: hd : 1/z * (↑n + (S − ↑n)) = ↑n * (1/z) + (S − ↑n) / z — after rw [hd], the re should be (↑n*(1/z) + (S−↑n)/z).re. Then Complex.add_re splits. But the displayed RHS shows `((↑n + (S − ↑n) − ↑n) / z).re` — the rewrite of (S − ↑n) got tangled: `hd`'s RHS `(S - ↑n) / z` — and then... hmm, actually looking: `((↑n + (S − ↑n) − ↑n) / z).re` = ((S)/z).re — this came from rw [hS] rewriting S as n + (S−n) INSIDE hd's already-applied rewrite! The rw sequence: [hf, hS, hd, ...] — hS rewrites S → ↑n + (S − ↑n) everywhere INCLUDING the `S − ↑n` inside hd's output? No wait — rw [hS] happens BEFORE hd. After rw [hf, hS]: goal has (1/z * (↑n + (S − ↑n))).re — but hS : S = ↑n + (S − ↑n) — rw [hS] rewrites S EVERYWHERE including the S inside "S − ↑n" itself?? rw rewrites all instances of the LHS pattern `S` — in the term `(1/z) * (↑n + (S - ↑n))`: the S inside `(S − ↑n)` also matches and gets rewritten: → `↑n + ((↑n + (S − ↑n)) − ↑n)`. That's the classic set-with-rw loop issue (only rewrites once, but messes the inner S). Result displayed: `((↑n + (S − ↑n) − ↑n)/z).re` ✓ exactly what happened.
Fix: don't rw [hS]; instead use conv to rewrite only the outer S, or restructure: since hf : 1 − wⁿ = (1/z)·S, rewrite goal's `1 − wⁿ` via hf, then need ((1/z)·S).re — write S = n + (S−n) via conv pattern: `conv_lhs => rw [hf]; pattern ((1/z) * S)`... simpler: avoid hS rewrite:
```
have hfre : ... := by
have hd : (1 / z) * ((n : ℂ) + (S - n)) = (n : ℂ) * (1 / z) + (S - n) / z := by
field_simp; ring
have hS2 : (1 : ℂ) - w ^ n = (1 / z) * ((n : ℂ) + (S - n)) := by
rw [hf]; congr 1; rw [hS] -- no: same issue
```
Cleanest: prove the final re-form directly:
```
have hfre : (1 - w ^ n).re = n * z.re / ‖z‖ ^ 2 + ((S - n) / z).re := by
have hd : (1 / z) * ((n : ℂ) + (S - n)) = (n : ℂ) * (1 / z) + (S - n) / z := by
field_simp; ring
have hS2 : (1 : ℂ) - w ^ n = (1 / z) * ((n : ℂ) + (S - n)) := by
rw [hf, show S = (n : ℂ) + (S - n) from by ring]
rw [hS2, hd, Complex.add_re, hre1]
```
The `show S = (n:ℂ) + (S − n) from by ring` — rw with this equation: rewrites S → ↑n + (S−↑n) — SAME looping issue!! Because the equation's LHS is `S` — it rewrites all S occurrences including inside RHS of itself? No — rw [h : S = X] rewrites occurrences of S in the GOAL; the goal `(1/z)·S` has ONE S; rewriting gives `(1/z)·(↑n + (S − ↑n))` — the new term contains S again (inside S−n) but rw does one pass: does rw rewrite the S inside the newly introduced X? rw does rewrite_all_occurrences of the LHS pattern in the goal — it does a single pass: finds all instances of S in the CURRENT goal, replaces them. After replacement, it doesn't re-scan. So `(1/z)·S` → `(1/z)·(↑n + (S − ↑n))` — ONE S in goal replaced by a term containing S — the result has S but rw is done ✓ no loop. So the earlier problem was different: the goal after rw [hf] was `(1 / z * S).re = ...` — ONE S — rw [hS] gives `(1/z * (↑n + (S − ↑n))).re` ✓ fine. THEN rw [hd]: pattern `1/z * (↑n + (S−↑n))` matches ✓ → `(↑n * (1/z) + (S − ↑n)/z).re` ✓. Then Complex.add_re ✓, hre1 ✓. Where did the tangle come from? The displayed goal: `... = ↑n * z.re/‖z‖² + ((↑n + (S − ↑n) − ↑n)/z).re` — the RHS of the GOAL (hfre's statement RHS `n·z.re/‖z‖² + ((S − n)/z).re`) got ITS S rewritten by rw [hS] too!! The statement's `((S − n)/z).re` contains S → became `((↑n + (S−↑n) − ↑n)/z).re`. So after hre1 rewrite, LHS = `↑n*z.re/‖z‖² + ((S−↑n)/z).re` vs goal `↑n*z.re/‖z‖² + ((↑n+(S−↑n)−↑n)/z).re` — mismatch (S−↑n) vs (↑n+(S−↑n)−↑n) — equal but not syntactically. Fix: `congr 1; congr 1; ring`? The remaining: ((S−↑n)/z).re = ((↑n+(S−↑n)−↑n)/z).re: `congr 1` twice → S−↑n = ↑n+(S−↑n)−↑n → ring. Or avoid rewriting the goal-RHS: do the rewrites only on LHS:
```
rw [show (1:ℂ) - w^n = (1/z) * S from hf]
conv_lhs => rw [show S = (n:ℂ) + (S - n) from by ring]
```
conv_lhs confines to LHS ✓. Then rw [hd, Complex.add_re, hre1] — hd/hre1/Complex.add_re patterns appear on both sides?? The goal RHS has ((S−n)/z).re — Complex.add_re would rewrite LHS only if... rw rewrites everywhere. ((S−↑n)/z).re is not of the form (a+b).re ✓ safe. hre1's pattern (↑n * (1/z)).re — appears only on LHS ✓. So:
```
have hfre : (1 - w ^ n).re = n * z.re / ‖z‖ ^ 2 + ((S - n) / z).re := by
have hd : (1 / z) * ((n : ℂ) + (S - n)) = (n : ℂ) * (1 / z) + (S - n) / z := by
field_simp; ring
rw [show (1 : ℂ) - w ^ n = (1 / z) * S from hf]
conv_lhs => rw [show S = (n : ℂ) + (S - n) from by ring, hd, Complex.add_re, hre1]
```
Hmm — rw inside conv_lhs with hd — hd's pattern `1/z * (↑n + (S−↑n))` ✓. Complex.add_re pattern (↑n*(1/z) + (S−↑n)/z).re ✓ → (↑n*(1/z)).re + ((S−↑n)/z).re; hre1: (↑n*(1/z)).re → ↑n*z.re/‖z‖² ✓. Then goal: LHS = ↑n*z.re/‖z‖² + ((S−↑n)/z).re, RHS = same ✓ rfl — but after conv_lhs the goal must be closed by rfl explicitly? conv_lhs changes the goal; after the conv block, if LHS ≡ RHS syntactically, Lean closes it automatically? No — need `all_goals rfl`? conv_lhs rewrites then the goal remains `X = X` — I think rw inside conv closes rfl goals automatically at the end? Not sure. Safer: end with no conv — do the conv rewrites then rfl:
```
rw [show (1 : ℂ) - w ^ n = (1 / z) * S from hf]
conv_lhs => rw [show S = (n : ℂ) + (S - n) from by ring, hd, Complex.add_re, hre1]
```
conv blocks auto-close if the goal becomes rfl? I believe after conv_lhs => rw [...], if the resulting goal is syntactic rfl, the block succeeds and closes it (rw closes rfl goals). Yes — rw closes goals that become rfl, including inside conv? Actually inside conv, after the conv block the outer tactic continues; if goal is `a = a` the conv block's result... let me just append nothing and see. Alternative without conv: use `nth_rewrite`:
```
rw [hf]
nth_rewrite 1 [show S = (n : ℂ) + (S - n) from by ring]
rw [hd, Complex.add_re, hre1]
```
nth_rewrite 1 [S-eq] — rewrites the FIRST occurrence of S in the goal — the goal after rw [hf]: `(1/z * S).re = ↑n*z.re/‖z‖² + ((S−↑n)/z).re` — occurrences of S: #1 in LHS product, #2 in RHS's (S−↑n). nth_rewrite 1 rewrites only #1 ✓✓. Then rw [hd, Complex.add_re, hre1] ✓ final rfl ✓. This is cleaner. But is occurrence #1 the LHS one? Order is by term traversal — the goal's LHS comes first ✓.
2. `div_le_div_right` unknown identifier (lines 166, 173, 182) — wrong name. The iff form: `div_le_div_right (hc : 0 < c) : a / c ≤ b / c ↔ a ≤ b` — hmm that exists? Apparently not under this name in this Mathlib. Modern names: `div_le_div_right` might be `div_le_div_iff_right`? or `div_le_div_right` exists in Order/Basic... The error says unknown. Candidates: `div_le_div_right`, `div_le_div_iff_right (hc : 0 < c) : a / c ≤ b / c ↔ a ≤ b` — I believe `div_le_div_iff_right` exists in recent Mathlib (there was a rename wave: le_div_iff, div_le_iff, div_le_div_iff_right). Also monotone version `div_le_div_of_nonneg_right`?? Unknown. Safest: avoid it — use `div_le_iff`/`le_div_iff` directly with mul:
For hA: |n·z.re/‖z‖²| ≤ n/‖z‖²: n·|z.re|/‖z‖² ≤ n/‖z‖² ⟺ n·|z.re| ≤ n (mul by ‖z‖² > 0):
```
apply (div_le_div_iff_of_nonneg ...)?
```
Simplest: `apply div_le_div_of_nonneg_right`? unknown too. Use: `by gcongr` — gcongr handles a/c ≤ b/c given a ≤ b ✓ robust:
hA: after the abs rewrites: goal |↑n| * |z.re| / |‖z‖^2| ≤ ↑n / ‖z‖^2: messy. Restructure hA entirely:
```
have hA : |n * z.re / ‖z‖ ^ 2| ≤ n / ‖z‖ ^ 2 := by
have e : n * z.re / ‖z‖ ^ 2 = (n * z.re) / ‖z‖ ^ 2 := by ring
rw [e, abs_div]
have e2 : |↑n * z.re| = n * |z.re| := by
rw [abs_mul, abs_of_nonneg hn0.le]
rw [e2, abs_of_nonneg (sq_nonneg ‖z‖)]
apply div_le_div_of_nonneg_right?
```
Let me use a uniform robust pattern via div_le_iff (which I'm confident exists: `div_le_iff (hc : 0 < c) : a / c ≤ b ↔ a ≤ b * c`):
```
rw [div_le_iff (by positivity : (0:ℝ) < ‖z‖ ^ 2)]
-- goal: n * |z.re| ≤ n * ‖z‖^2 / ‖z‖^2... no: (n/‖z‖²) * ‖z‖² = n
have : (n / ‖z‖ ^ 2) * ‖z‖ ^ 2 = n := by field_simp
rw [this]
apply mul_le_mul_of_nonneg_left _ hn0.le
exact abs_le.mpr ⟨hzre0, hzre1⟩
```
div_le_iff : a / c ≤ b ↔ a ≤ b * c (hc : 0 < c) — signature `div_le_iff (hc : 0 < c) : a / c ≤ b ↔ a ≤ b * c`? There's `div_le_iff₀`? In ordered field: `div_le_iff (hc : 0 < c) : a / c ≤ b ↔ a ≤ b * c` ✓ exists (or div_le_iff₀ — I'll try div_le_iff, fallback div_le_iff₀).
Same for hB's step: `‖S−n‖/‖z‖ ≤ (n²/‖z‖)/‖z‖` — via div_le_iff:
```
have h2 : ‖(S - n) / z‖ ≤ (n ^ 2 / ‖z‖) / ‖z‖ := by
rw [norm_div, div_le_iff hzn]
rw [← div_div] -- hmm target: ‖S−n‖ ≤ (n²/‖z‖/‖z‖)*‖z‖ = n²/‖z‖
have e : (n ^ 2 / ‖z‖ / ‖z‖) * ‖z‖ = n ^ 2 / ‖z‖ := by field_simp
rw [e]
exact hSn
```
Wait — after rw [norm_div]: goal ‖S−n‖/‖z‖ ≤ (n²/‖z‖)/‖z‖: div_le_iff hzn : a/‖z‖ ≤ b ↔ a ≤ b*‖z‖: goal: ‖S−n‖ ≤ ((n²/‖z‖)/‖z‖)*‖z‖ = n²/‖z‖: field_simp proves the product identity, then hSn ✓.
And the final step:
```
_ ≤ 2 * n ^ 2 / ‖z‖ ^ 2 := by
rw [div_le_iff (by positivity)]
have e : (2 * n ^ 2 / ‖z‖ ^ 2) * ‖z‖ ^ 2 = 2 * n ^ 2 := by field_simp
rw [e]
linarith [hnn]
```
Hmm — goal: (n + n²)/‖z‖² ≤ 2n²/‖z‖²: div_le_iff: (n+n²) ≤ (2n²/‖z‖²)·‖z‖² = 2n²: linarith with hnn : n ≤ n² ✓.
3. `abs_add` unknown (line 179) — the name for |a+b| ≤ |a|+|b| is `abs_add` in Algebra/Order/AbsoluteValue or `abs_add` for ordered rings — apparently unknown here?? Weird — abs_add is very standard. Maybe it's `abs_add` in a namespace not opened... I have `open ... Topology` etc. Try `abs_add` — error says unknown identifier. Alternatives: `abs_add_le`, `abs_add'`... For ℝ: `abs_add (a b : ℝ) : |a + b| ≤ |a| + |b|` — it's in Mathlib/Algebra/Order/AbsoluteValue? or Mathlib/Algebra/Order/Abs. Hmm — actually `abs_add` IS standard: `theorem abs_add (a b : α) : |a + b| ≤ |a| + |b|` in Algebra/Order/Unbundled/Abs.lean. Maybe unknown because of an open collision (Topology has abs_add? no). Wait — maybe the issue: `open Zeta23 Complex Filter Topology` — maybe one of these shadows abs_add? Unlikely. The error: `unknown identifier abs_add` — maybe in this Mathlib version it's named differently: check `abs_add_le`? Let me just use `(abs_add _ _)` replaced by `abs_add_le`? Hmm. Or norm: for ℝ, |x| = ‖x‖: `norm_add_le`. Let me check names via grep quickly for all three unknowns.
Good progress — hre1 proved. Three name issues left. Checking the exact names in this Mathlib.
tool: Bash
input
{
"command": "cd /d/Python/Quantum/zeta-23-lean/.lake/packages/mathlib && grep -rn \"theorem div_le_iff \\|lemma div_le_iff \\|theorem div_le_iff\u2080\\|lemma div_le_iff\u2080\" Mathlib/Algebra/Order/Field/Basic.lean Mathlib/Algebra/Order/Unbundled/Basic.lean 2>/dev/null | head -4; grep -rn \"theorem abs_add \\|lemma abs_add \\|abs_add_le\\b\" Mathlib/Algebra/Order/AbsoluteValue.lean Mathlib/Algebra/Order/Unbundled/Abs.lean 2>/dev/null | head -4; grep -rn \"theorem div_le_div_iff_right\\|lemma div_le_div_iff_right\" Mathlib/ --include=*.lean | head -2",
"description": "Check div_le_iff, abs_add, div_le_div_iff_right names"
}
raw content_json (database row)
[{"type":"thinking","thinking":"Progress — hre1 is now proved. Remaining:\n\n1. hfre (line 158-160): after `rw [hf, hS, hd, Complex.add_re, hre1]` — the goal:\n`↑n * z.re / ‖z‖ ^ 2 + ((S - ↑n) / z).re = ↑n * z.re / ‖z‖ ^ 2 + ((↑n + (S - ↑n) - ↑n) / z).re`\nThe LHS is the goal's RHS from hfre's statement; the RHS has `((↑n + (S − ↑n) − ↑n)/z).re` — because hd rewrote (1/z)*(n + (S−n)) = n*(1/z) + (S−n)/z — WAIT no: hd : 1/z * (↑n + (S − ↑n)) = ↑n * (1/z) + (S − ↑n) / z — after rw [hd], the re should be (↑n*(1/z) + (S−↑n)/z).re. Then Complex.add_re splits. But the displayed RHS shows `((↑n + (S − ↑n) − ↑n) / z).re` — the rewrite of (S − ↑n) got tangled: `hd`'s RHS `(S - ↑n) / z` — and then... hmm, actually looking: `((↑n + (S − ↑n) − ↑n) / z).re` = ((S)/z).re — this came from rw [hS] rewriting S as n + (S−n) INSIDE hd's already-applied rewrite! The rw sequence: [hf, hS, hd, ...] — hS rewrites S → ↑n + (S − ↑n) everywhere INCLUDING the `S − ↑n` inside hd's output? No wait — rw [hS] happens BEFORE hd. After rw [hf, hS]: goal has (1/z * (↑n + (S − ↑n))).re — but hS : S = ↑n + (S − ↑n) — rw [hS] rewrites S EVERYWHERE including the S inside \"S − ↑n\" itself?? rw rewrites all instances of the LHS pattern `S` — in the term `(1/z) * (↑n + (S - ↑n))`: the S inside `(S − ↑n)` also matches and gets rewritten: → `↑n + ((↑n + (S − ↑n)) − ↑n)`. That's the classic set-with-rw loop issue (only rewrites once, but messes the inner S). Result displayed: `((↑n + (S − ↑n) − ↑n)/z).re` ✓ exactly what happened.\n\nFix: don't rw [hS]; instead use conv to rewrite only the outer S, or restructure: since hf : 1 − wⁿ = (1/z)·S, rewrite goal's `1 − wⁿ` via hf, then need ((1/z)·S).re — write S = n + (S−n) via conv pattern: `conv_lhs => rw [hf]; pattern ((1/z) * S)`... simpler: avoid hS rewrite: \n```\nhave hfre : ... := by\n have hd : (1 / z) * ((n : ℂ) + (S - n)) = (n : ℂ) * (1 / z) + (S - n) / z := by\n field_simp; ring\n have hS2 : (1 : ℂ) - w ^ n = (1 / z) * ((n : ℂ) + (S - n)) := by\n rw [hf]; congr 1; rw [hS] -- no: same issue\n```\nCleanest: prove the final re-form directly:\n```\nhave hfre : (1 - w ^ n).re = n * z.re / ‖z‖ ^ 2 + ((S - n) / z).re := by\n have hd : (1 / z) * ((n : ℂ) + (S - n)) = (n : ℂ) * (1 / z) + (S - n) / z := by\n field_simp; ring\n have hS2 : (1 : ℂ) - w ^ n = (1 / z) * ((n : ℂ) + (S - n)) := by\n rw [hf, show S = (n : ℂ) + (S - n) from by ring]\n rw [hS2, hd, Complex.add_re, hre1]\n```\nThe `show S = (n:ℂ) + (S − n) from by ring` — rw with this equation: rewrites S → ↑n + (S−↑n) — SAME looping issue!! Because the equation's LHS is `S` — it rewrites all S occurrences including inside RHS of itself? No — rw [h : S = X] rewrites occurrences of S in the GOAL; the goal `(1/z)·S` has ONE S; rewriting gives `(1/z)·(↑n + (S − ↑n))` — the new term contains S again (inside S−n) but rw does one pass: does rw rewrite the S inside the newly introduced X? rw does rewrite_all_occurrences of the LHS pattern in the goal — it does a single pass: finds all instances of S in the CURRENT goal, replaces them. After replacement, it doesn't re-scan. So `(1/z)·S` → `(1/z)·(↑n + (S − ↑n))` — ONE S in goal replaced by a term containing S — the result has S but rw is done ✓ no loop. So the earlier problem was different: the goal after rw [hf] was `(1 / z * S).re = ...` — ONE S — rw [hS] gives `(1/z * (↑n + (S − ↑n))).re` ✓ fine. THEN rw [hd]: pattern `1/z * (↑n + (S−↑n))` matches ✓ → `(↑n * (1/z) + (S − ↑n)/z).re` ✓. Then Complex.add_re ✓, hre1 ✓. Where did the tangle come from? The displayed goal: `... = ↑n * z.re/‖z‖² + ((↑n + (S − ↑n) − ↑n)/z).re` — the RHS of the GOAL (hfre's statement RHS `n·z.re/‖z‖² + ((S − n)/z).re`) got ITS S rewritten by rw [hS] too!! The statement's `((S − n)/z).re` contains S → became `((↑n + (S−↑n) − ↑n)/z).re`. So after hre1 rewrite, LHS = `↑n*z.re/‖z‖² + ((S−↑n)/z).re` vs goal `↑n*z.re/‖z‖² + ((↑n+(S−↑n)−↑n)/z).re` — mismatch (S−↑n) vs (↑n+(S−↑n)−↑n) — equal but not syntactically. Fix: `congr 1; congr 1; ring`? The remaining: ((S−↑n)/z).re = ((↑n+(S−↑n)−↑n)/z).re: `congr 1` twice → S−↑n = ↑n+(S−↑n)−↑n → ring. Or avoid rewriting the goal-RHS: do the rewrites only on LHS: \n```\nrw [show (1:ℂ) - w^n = (1/z) * S from hf]\nconv_lhs => rw [show S = (n:ℂ) + (S - n) from by ring]\n```\nconv_lhs confines to LHS ✓. Then rw [hd, Complex.add_re, hre1] — hd/hre1/Complex.add_re patterns appear on both sides?? The goal RHS has ((S−n)/z).re — Complex.add_re would rewrite LHS only if... rw rewrites everywhere. ((S−↑n)/z).re is not of the form (a+b).re ✓ safe. hre1's pattern (↑n * (1/z)).re — appears only on LHS ✓. So:\n```\nhave hfre : (1 - w ^ n).re = n * z.re / ‖z‖ ^ 2 + ((S - n) / z).re := by\n have hd : (1 / z) * ((n : ℂ) + (S - n)) = (n : ℂ) * (1 / z) + (S - n) / z := by\n field_simp; ring\n rw [show (1 : ℂ) - w ^ n = (1 / z) * S from hf]\n conv_lhs => rw [show S = (n : ℂ) + (S - n) from by ring, hd, Complex.add_re, hre1]\n```\nHmm — rw inside conv_lhs with hd — hd's pattern `1/z * (↑n + (S−↑n))` ✓. Complex.add_re pattern (↑n*(1/z) + (S−↑n)/z).re ✓ → (↑n*(1/z)).re + ((S−↑n)/z).re; hre1: (↑n*(1/z)).re → ↑n*z.re/‖z‖² ✓. Then goal: LHS = ↑n*z.re/‖z‖² + ((S−↑n)/z).re, RHS = same ✓ rfl — but after conv_lhs the goal must be closed by rfl explicitly? conv_lhs changes the goal; after the conv block, if LHS ≡ RHS syntactically, Lean closes it automatically? No — need `all_goals rfl`? conv_lhs rewrites then the goal remains `X = X` — I think rw inside conv closes rfl goals automatically at the end? Not sure. Safer: end with no conv — do the conv rewrites then rfl:\n```\n rw [show (1 : ℂ) - w ^ n = (1 / z) * S from hf]\n conv_lhs => rw [show S = (n : ℂ) + (S - n) from by ring, hd, Complex.add_re, hre1]\n```\nconv blocks auto-close if the goal becomes rfl? I believe after conv_lhs => rw [...], if the resulting goal is syntactic rfl, the block succeeds and closes it (rw closes rfl goals). Yes — rw closes goals that become rfl, including inside conv? Actually inside conv, after the conv block the outer tactic continues; if goal is `a = a` the conv block's result... let me just append nothing and see. Alternative without conv: use `nth_rewrite`:\n```\n rw [hf]\n nth_rewrite 1 [show S = (n : ℂ) + (S - n) from by ring]\n rw [hd, Complex.add_re, hre1]\n```\nnth_rewrite 1 [S-eq] — rewrites the FIRST occurrence of S in the goal — the goal after rw [hf]: `(1/z * S).re = ↑n*z.re/‖z‖² + ((S−↑n)/z).re` — occurrences of S: #1 in LHS product, #2 in RHS's (S−↑n). nth_rewrite 1 rewrites only #1 ✓✓. Then rw [hd, Complex.add_re, hre1] ✓ final rfl ✓. This is cleaner. But is occurrence #1 the LHS one? Order is by term traversal — the goal's LHS comes first ✓.\n\n2. `div_le_div_right` unknown identifier (lines 166, 173, 182) — wrong name. The iff form: `div_le_div_right (hc : 0 < c) : a / c ≤ b / c ↔ a ≤ b` — hmm that exists? Apparently not under this name in this Mathlib. Modern names: `div_le_div_right` might be `div_le_div_iff_right`? or `div_le_div_right` exists in Order/Basic... The error says unknown. Candidates: `div_le_div_right`, `div_le_div_iff_right (hc : 0 < c) : a / c ≤ b / c ↔ a ≤ b` — I believe `div_le_div_iff_right` exists in recent Mathlib (there was a rename wave: le_div_iff, div_le_iff, div_le_div_iff_right). Also monotone version `div_le_div_of_nonneg_right`?? Unknown. Safest: avoid it — use `div_le_iff`/`le_div_iff` directly with mul:\nFor hA: |n·z.re/‖z‖²| ≤ n/‖z‖²: n·|z.re|/‖z‖² ≤ n/‖z‖² ⟺ n·|z.re| ≤ n (mul by ‖z‖² > 0): \n```\napply (div_le_div_iff_of_nonneg ...)? \n```\nSimplest: `apply div_le_div_of_nonneg_right`? unknown too. Use: `by gcongr` — gcongr handles a/c ≤ b/c given a ≤ b ✓ robust:\nhA: after the abs rewrites: goal |↑n| * |z.re| / |‖z‖^2| ≤ ↑n / ‖z‖^2: messy. Restructure hA entirely:\n```\nhave hA : |n * z.re / ‖z‖ ^ 2| ≤ n / ‖z‖ ^ 2 := by\n have e : n * z.re / ‖z‖ ^ 2 = (n * z.re) / ‖z‖ ^ 2 := by ring\n rw [e, abs_div]\n have e2 : |↑n * z.re| = n * |z.re| := by\n rw [abs_mul, abs_of_nonneg hn0.le]\n rw [e2, abs_of_nonneg (sq_nonneg ‖z‖)]\n apply div_le_div_of_nonneg_right? \n```\nLet me use a uniform robust pattern via div_le_iff (which I'm confident exists: `div_le_iff (hc : 0 < c) : a / c ≤ b ↔ a ≤ b * c`):\n```\n rw [div_le_iff (by positivity : (0:ℝ) < ‖z‖ ^ 2)]\n -- goal: n * |z.re| ≤ n * ‖z‖^2 / ‖z‖^2... no: (n/‖z‖²) * ‖z‖² = n\n have : (n / ‖z‖ ^ 2) * ‖z‖ ^ 2 = n := by field_simp\n rw [this]\n apply mul_le_mul_of_nonneg_left _ hn0.le\n exact abs_le.mpr ⟨hzre0, hzre1⟩\n```\ndiv_le_iff : a / c ≤ b ↔ a ≤ b * c (hc : 0 < c) — signature `div_le_iff (hc : 0 < c) : a / c ≤ b ↔ a ≤ b * c`? There's `div_le_iff₀`? In ordered field: `div_le_iff (hc : 0 < c) : a / c ≤ b ↔ a ≤ b * c` ✓ exists (or div_le_iff₀ — I'll try div_le_iff, fallback div_le_iff₀).\n\nSame for hB's step: `‖S−n‖/‖z‖ ≤ (n²/‖z‖)/‖z‖` — via div_le_iff:\n```\nhave h2 : ‖(S - n) / z‖ ≤ (n ^ 2 / ‖z‖) / ‖z‖ := by\n rw [norm_div, div_le_iff hzn]\n rw [← div_div] -- hmm target: ‖S−n‖ ≤ (n²/‖z‖/‖z‖)*‖z‖ = n²/‖z‖\n have e : (n ^ 2 / ‖z‖ / ‖z‖) * ‖z‖ = n ^ 2 / ‖z‖ := by field_simp\n rw [e]\n exact hSn\n```\nWait — after rw [norm_div]: goal ‖S−n‖/‖z‖ ≤ (n²/‖z‖)/‖z‖: div_le_iff hzn : a/‖z‖ ≤ b ↔ a ≤ b*‖z‖: goal: ‖S−n‖ ≤ ((n²/‖z‖)/‖z‖)*‖z‖ = n²/‖z‖: field_simp proves the product identity, then hSn ✓.\n\nAnd the final step:\n```\n _ ≤ 2 * n ^ 2 / ‖z‖ ^ 2 := by\n rw [div_le_iff (by positivity)]\n have e : (2 * n ^ 2 / ‖z‖ ^ 2) * ‖z‖ ^ 2 = 2 * n ^ 2 := by field_simp\n rw [e]\n linarith [hnn]\n```\nHmm — goal: (n + n²)/‖z‖² ≤ 2n²/‖z‖²: div_le_iff: (n+n²) ≤ (2n²/‖z‖²)·‖z‖² = 2n²: linarith with hnn : n ≤ n² ✓.\n\n3. `abs_add` unknown (line 179) — the name for |a+b| ≤ |a|+|b| is `abs_add` in Algebra/Order/AbsoluteValue or `abs_add` for ordered rings — apparently unknown here?? Weird — abs_add is very standard. Maybe it's `abs_add` in a namespace not opened... I have `open ... Topology` etc. Try `abs_add` — error says unknown identifier. Alternatives: `abs_add_le`, `abs_add'`... For ℝ: `abs_add (a b : ℝ) : |a + b| ≤ |a| + |b|` — it's in Mathlib/Algebra/Order/AbsoluteValue? or Mathlib/Algebra/Order/Abs. Hmm — actually `abs_add` IS standard: `theorem abs_add (a b : α) : |a + b| ≤ |a| + |b|` in Algebra/Order/Unbundled/Abs.lean. Maybe unknown because of an open collision (Topology has abs_add? no). Wait — maybe the issue: `open Zeta23 Complex Filter Topology` — maybe one of these shadows abs_add? Unlikely. The error: `unknown identifier abs_add` — maybe in this Mathlib version it's named differently: check `abs_add_le`? Let me just use `(abs_add _ _)` replaced by `abs_add_le`? Hmm. Or norm: for ℝ, |x| = ‖x‖: `norm_add_le`. Let me check names via grep quickly for all three unknowns.","signature":""},{"type":"text","text":"Good progress — hre1 proved. Three name issues left. Checking the exact names in this Mathlib."},{"type":"tool_use","id":"Bash_114","name":"Bash","input":{"command":"cd /d/Python/Quantum/zeta-23-lean/.lake/packages/mathlib && grep -rn \"theorem div_le_iff \\|lemma div_le_iff \\|theorem div_le_iff₀\\|lemma div_le_iff₀\" Mathlib/Algebra/Order/Field/Basic.lean Mathlib/Algebra/Order/Unbundled/Basic.lean 2>/dev/null | head -4; grep -rn \"theorem abs_add \\|lemma abs_add \\|abs_add_le\\b\" Mathlib/Algebra/Order/AbsoluteValue.lean Mathlib/Algebra/Order/Unbundled/Abs.lean 2>/dev/null | head -4; grep -rn \"theorem div_le_div_iff_right\\|lemma div_le_div_iff_right\" Mathlib/ --include=*.lean | head -2","description":"Check div_le_iff, abs_add, div_le_div_iff_right names"},"extra_content":null}]