DL0090

matrix_integer_square_index_width_nonzero

Alpha v34 independently verified · alpha_closed; checked-use authorized; not Stable

An actual index in a square prefix proves its row width is nonzero; zero-dimensional bounds remain genuinely vacuous.

Current library: Alpha v34, 4,223 checked-use theorems; Stable remains 432. Historical first admissions, original proof editions, and non-admitted aliases are preserved. Exact original first-admission records.

Exact expanded first-order arithmetic statement

forall q i. (exists mdr_gap_square_index. mdr_gap_square_index + S (i) = (q * q)) -> ~(q = 0)

Constructive proof overview

Generated structural guide

An actual index in a square prefix proves its row width is nonzero; zero-dimensional bounds remain genuinely vacuous.

The unchanged tactic script uses 1 declared prerequisite and contains 12 exact native proof lines.

Alpha v34 checked-use · first admitted v27 · independently kernel and Lean verified; not Stable

Proof neighborhood

Direct dependencies

Direct dependents

Formal native tactic body

Dependencies are introduced as named hypotheses before line 1. Local theorem links identify exact declared prerequisites. This exact body belongs to a complete independently kernel-checked constructive proof bundle and has Alpha checked-use authority; it does not imply Stable membership.

Read the argument

Proof checkpoints

12 script commands · 2 reading checkpoints · 1 local claims

This is a reading aid, not a new proof or a proof-tree certificate. Checkpoint groups are consecutive commands, not inferred branch boundaries. Every step links to the preserved script.

Named ingredients (1)
01Fix variables and assumptionsL1–4

Work with arbitrary variables or the premises of the current implication.

  1. L1
    intro q
  2. L2
    intro i
  3. L3
    intro hi
  4. L4
    intro hzero
02Establish hlengthL5–12

Establish this local claim before using it. It is not an additional assumption. The following proof commands apply PA5.

  1. L5
    have hlength : q * q = 0
  2. L6
    rewrite hzero
  3. L7
    rewrite hzero
  4. L8
    apply PA5
  5. L9
    rewrite hlength at hi
  6. L10
    specialize matrix_rank_no_index_below_zero (i)
  7. L11
    apply matrix_rank_no_index_below_zero
  8. L12
    exact hi

Library-wide reading audit

Original exact command ledger · 12 lines
  1. 0001intro q
  2. 0002intro i
  3. 0003intro hi
  4. 0004intro hzero
  5. 0005have hlength : q * q = 0
  6. 0006rewrite hzero
  7. 0007rewrite hzero
  8. 0008apply PA5
  9. 0009rewrite hlength at hi
  10. 0010specialize matrix_rank_no_index_below_zero (i)
  11. 0011apply matrix_rank_no_index_below_zero
  12. 0012exact hi