Alphabeta Math
ExampleConstruction: AI-generatedVerification: AI-generatedPipeline-generatedjudge pass (gpt-6-luna)
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 two-state POMDP update changes a three-to-one prior to nine-to-one

Example

Let S={s0,s1}, A={a}, Ω={x,y}, reward alphabet {0}, and horizon H=1 with γ=1. For each i∈{0,1}, the joint next-state/reward law assigns probability one to (si,0) from (si,a), so the hidden state remains fixed and the reward is zero. Let b0(s0)=3/4, b0(s1)=1/4, and set O(x∣s0)=3/4, O(x∣s1)=1/4, O(y∣s0)=1/4, and O(y∣s1)=3/4. The probability of observing x is 5/8, and after x the belief is b1(s0)=9/10, b1(s1)=1/10.

Facts & Assumptions

Given: The finite POMDP model in the example and the observation x.

[F1]

The state transition is the marginal of the specified finite joint reward-transition law, and each O(⋅∣s′) is a probability distribution. Finite partially observable Markov decision process

[F2]

The predicted belief is bˉ(s′)=∑sT(s′∣s,a)b(s), the observation probability is q(o∣b,a)=∑s′O(o∣s′)bˉ(s′), and the positive-probability update is τ(b,a,o)(s′)=O(o∣s′)bˉ(s′)/q(o∣b,a). Belief states and the finite Bayes filter

[F3]

The predicted law and observation probabilities normalize, and τ is a probability vector when q>0. The finite POMDP Bayes filter is a probability kernel

[F4]

Finite sums over finite index sets are well defined and enumeration-independent. The sum ∑i∈Sai over a finite index set, and its product form

Verification

1.1givenF1F2

The transition marginal is the identity on S, so the predicted law after action a is bˉ1(s0)=3/4 and bˉ1(s1)=1/4.

2.1step 1.1F2F4algebra

The observation normalizer is q(x∣b0,a)=(3/4)(3/4)+(1/4)(1/4)=9/16+1/16=5/8>0.

3.1step 1.1step 2.1F2F3algebra∎

The update gives b1(s0)=(3/4)(3/4)/(5/8)=(9/16)/(10/16)=9/10 and b1(s1)=(1/4)(1/4)/(5/8)=(1/16)/(10/16)=1/10. Both coordinates are nonnegative and sum to one, in agreement with [F3].

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