Alphabeta Math
ExampleConstruction: Literature-sourcedVerification: AI-generatedPipeline-generated
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.

A state-action pair that is never visited keeps its initialization

Example

Consider the continuing finite MDP with one state s, actions a,b, discount γ=0, and deterministic transitions back to s. Action a always gives reward 1 and action b always gives reward 0. Initialize Q0(s,a)=0 and Q0(s,b)=−1, and let the behavior rule choose a at every time. Under tabular Q-learning, the pair (s,b) is never visited, so its estimate remains −1 forever, although the optimal action values are Q∗(s,a)=1 and Q∗(s,b)=0.

Facts & Assumptions

Given: The one-state MDP, its deterministic rewards, γ=0, the initial table, behavior rule, and Q-learning updates in the Example.

[F1]

Finite Markov decision process with joint reward-transition law: each state-action pair has the stated joint next-state/reward probability mass.

[F2]

Tabular Q-learning: only the visited state-action coordinate is changed by an update.

[F3]

Optimal action-value Bellman operator: (HQ)(s,a)=∑s′,ρp(s′,ρ∣s,a)[ρ+γmax⁡bQ(s′,b)].

Proof

1.1givenF2induction

The behavior rule always selects a, so no update ever changes coordinate (s,b). By [F2] and induction on n, Qn(s,b)=Q0(s,b)=−1 for every n.

2.1givenF1F3step 1.1algebra∎

At γ=0, [F3] gives (HQ)(s,a)=1 and (HQ)(s,b)=0 for every table Q, because the two rewards are deterministic. Thus the unique Bellman fixed point has Q∗(s,b)=0, while step 1.1 shows the learned coordinate is always −1. The unvisited coordinate is not identified by these data.

Depends on

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