Alphabeta Math
LemmaStatement: AI-adaptedProof: AI-generatedSession-authored (Fable 5 assisted)precheck passjudge pass (openai/gpt-5.4)audited 2026-07-24
How statement and proof provenance work

The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.

  • Literature-sourced — the exact statement appears in a cited source; only wording and notation differ.
  • AI-adapted — a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
  • AI-generated — a genuinely novel statement formulated by AI, with no source for the claim itself.

These labels describe origin, not correctness: citations and verification chips remain separate evidence.

The rationals are Archimedean

Statement

For every rational xx there is a natural number nn with x<nx < n. Consequently, for every rational ε>0\varepsilon > 0 there is a natural n1n \ge 1 with 1/n<ε1/n < \varepsilon.

Facts & Assumptions

Given: A rational x=[(a,b)]x = [(a,b)] with b>0b > 0.

[L1]

The order and arithmetic of Q\mathbb{Q} (The rationals form a totally ordered field).

[L2]

Integer facts: positive integers are exactly ι(m)\iota(m) with m1m \ge 1 natural; nonnegative integers are the image of N\mathbb{N}; the embeddings preserve arithmetic and order (The naturals embed in the integers, The integers embed in the rationals, The integers form a totally ordered ring).

Proof

technique · direct
1.1

Since b>0b > 0, bb lies in the image of N\mathbb{N} and b1b \ge 1.

L2
1.2

If a0a \le 0 set k=0k = 0; otherwise aa is a positive integer, so a=ι(k)a = \iota(k) for some natural k1k \ge 1. In both cases aka \le k (as integers).

L2
2.1

Then a<k+1a < k + 1 and, since b1b \ge 1 and k+1>0k+1 > 0, also k+1(k+1)bk + 1 \le (k+1)b.

step 1.1step 1.2L2
3.1

Hence a<(k+1)ba < (k+1)b, and dividing by b>0b > 0 (order-scaling in the definition of the rational order), x=[(a,b)]<[((k+1)b,b)]=k+1=:nx = [(a,b)] < [( (k+1)b,\, b)] = k+1 =: n.

step 2.1L1
4.1

For rational ε>0\varepsilon > 0: apply the above to x=1/εx = 1/\varepsilon to get nn with 1/ε<n1/\varepsilon < n, hence 1/n<ε1/n < \varepsilon.

step 3.1L1

Depends on

Used by

Dependency tree · next 3 levels

Direct dependencies and their dependencies through the next three levels: 42 results over 16 levels. An arrow runs from a result to what uses it, and this result sits at the bottom with a heavier outline. Click the chart to enlarge it.

Sources