# Question 4997: Recording Codes and Outcome Fibers

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This teaching derivation has second-context AI mathematical and bilingual semantic review, limited to the model and assumptions stated in this question. It has no human review or new Lean proof and does not promote the original question or MKO to Canonical truth.

R0008-04997 · q-20261008-advance-20261011-r06-sample-space-0047



## Original question and givens

Elementary outcomes are Fin(4)={0,…,3}, with recording=[-21, 0, -21, 21] in original index order. Give (increasing distinct recording codes, aligned original-index fiber lists), sorting each fiber increasingly.


- G001 — Elementary outcomes are Fin(4)={0,…,3}, with recording=[-21, 0, -21, 21] in original index order. Give (increasing distinct recording codes, aligned original-index fiber lists), sorting each fiber increasingly.





## Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.


- [mko-sample-space](https://ocme.evemisslab.com/en/mko/mko-sample-space/)





## Step-by-step derivation

S001 · impliesBefore

explicit finite possible-outcome protocol

After

no probability law,equiprobability or independence inferred

Conditions: none

These tasks list possible outcomes,recordings or event membership without assigning probabilities.All combinations being possible does not imply equiprobability or independence.

Step identifiers and dependenciesRule: possible_outcomes_not_probabilities · Uses: G001





S002 · impliesBefore

original outcome index=0∈[0, 1, 2, 3]

After

recorded code=-21

Conditions: none

Each original outcome has one code;different outcomes may share a code.Codes do not redefine original indices.

Step identifiers and dependenciesRule: recording_total_mapping_row · Uses: G001, S001





S003 · impliesBefore

original outcome index=1∈[0, 1, 2, 3]

After

recorded code=0

Conditions: none

Each original outcome has one code;different outcomes may share a code.Codes do not redefine original indices.

Step identifiers and dependenciesRule: recording_total_mapping_row · Uses: G001, S002





S004 · impliesBefore

original outcome index=2∈[0, 1, 2, 3]

After

recorded code=-21

Conditions: none

Each original outcome has one code;different outcomes may share a code.Codes do not redefine original indices.

Step identifiers and dependenciesRule: recording_total_mapping_row · Uses: G001, S003





S005 · impliesBefore

original outcome index=3∈[0, 1, 2, 3]

After

recorded code=21

Conditions: none

Each original outcome has one code;different outcomes may share a code.Codes do not redefine original indices.

Step identifiers and dependenciesRule: recording_total_mapping_row · Uses: G001, S004





S006 · impliesBefore

recorded code=-21

After

[0, 2]

Conditions: none

List all original indices mapping to this code and align fibers with the sorted code list.

Step identifiers and dependenciesRule: recording_preimage_fiber · Uses: G001, S005





S007 · impliesBefore

recorded code=0

After

[1]

Conditions: none

List all original indices mapping to this code and align fibers with the sorted code list.

Step identifiers and dependenciesRule: recording_preimage_fiber · Uses: G001, S006





S008 · impliesBefore

recorded code=21

After

[3]

Conditions: none

List all original indices mapping to this code and align fibers with the sorted code list.

Step identifiers and dependenciesRule: recording_preimage_fiber · Uses: G001, S007









## Reverse checks


- S008 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S007 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S006 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S005 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S004 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S003 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S002 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.





## Result

([-21, 0, 21], [[0, 2], [1], [3]])

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.





## This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
- input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
- original question SHA-256: 5693527f69d1ab33e10d8c05364a0994fe2de138795f01b9de2a42f3cef3790a
- candidate record SHA-256: f203669f0d4865baea6ae718662b93190f61edafe5423e1eb5bebd140c22923c
- semantic review receipt SHA-256: b6e05a3e8193a93db505dbf337528fca72e2e41528b1e92b698a3f0683d74289
- question-first witness SHA-256: caa8693baf0b91acd09a20215d1aa6954ae513fc0b0814f26ac1c8c834b60d67
- Lean: NOT_RUN · human review: NOT_PERFORMED

[Same-source full JSON](https://ocme.evemisslab.com/data/question-derivations/questions/q-20261008-advance-20261011-r06-sample-space-0047.json)




