FS003P

four_square_lagrange

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

Lagrange's complete four-square theorem: every natural number has an unconditionally constructive, independently kernel-checked representation as a sum of four natural squares.

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 n. (exists fsl_a_fslf_natural fsl_b_fslf_natural fsl_c_fslf_natural fsl_d_fslf_natural. (n) = fsl_a_fslf_natural * fsl_a_fslf_natural + fsl_b_fslf_natural * fsl_b_fslf_natural + fsl_c_fslf_natural * fsl_c_fslf_natural + fsl_d_fslf_natural * fsl_d_fslf_natural)

Constructive proof overview

Generated structural guide

Lagrange's complete four-square theorem: every natural number has an unconditionally constructive, independently kernel-checked representation as a sum of four natural squares.

The unchanged tactic script uses 2 declared prerequisites and contains 2 exact native proof lines.

dependency-curried kernel-checked theorem body; Alpha enrollment and checked-use authority follow separately sealed release evidence; Stable membership remains unchanged

Proof neighborhood

Direct dependencies

Direct dependents

none

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

2 script commands · 1 reading checkpoints · 0 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 (2)
01Use earlier factsL1–2

Instantiate or apply named facts and discharge the corresponding proof obligations.

  1. L1
    apply four_square_lagrange_from_all_primes
  2. L2
    exact four_square_prime_representation

Library-wide reading audit

Original exact command ledger · 2 lines
  1. 0001apply four_square_lagrange_from_all_primes
  2. 0002exact four_square_prime_representation