# Question 5238: Two Finite Principal-Filter Composition Images

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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.

R0009-05238 · q-20261008-advance-20261011-r07-tends-to-relation-0088



## Original question and givens

The complete total map f:Fin(8)→Fin(8) has images=[7, 6, 5, 4, 3, 2, 1, 0] indexed from 0; Fin(8)={0,…,7}. Every table entry must lie in the target type. S=[2, 3]. principal(S) contains all source subsets containing S; the empty generator is allowed, and no NeBot premise is added. The complete map g:Fin(8)→Fin(8) has after=[7, 6, 5, 4, 3, 2, 1, 0]. Give ((g∘f)(S), g(f(S))) as complete increasing sets.


- G001 — The complete total map f:Fin(8)→Fin(8) has images=[7, 6, 5, 4, 3, 2, 1, 0] indexed from 0; Fin(8)={0,…,7}. Every table entry must lie in the target type. S=[2, 3]. principal(S) contains all source subsets containing S; the empty generator is allowed, and no NeBot premise is added. The complete map g:Fin(8)→Fin(8) has after=[7, 6, 5, 4, 3, 2, 1, 0]. Give ((g∘f)(S), g(f(S))) as complete increasing sets.





## 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-tends-to-relation](https://ocme.evemisslab.com/en/mko/mko-tends-to-relation/)





## Step-by-step derivation

S001 · impliesBefore

source index=0∈Fin(8)

After

image=7∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_principal_map_row · Uses: G001





S002 · impliesBefore

source index=1∈Fin(8)

After

image=6∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S003 · impliesBefore

source index=2∈Fin(8)

After

image=5∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S004 · impliesBefore

source index=3∈Fin(8)

After

image=4∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S005 · impliesBefore

source index=4∈Fin(8)

After

image=3∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S006 · impliesBefore

source index=5∈Fin(8)

After

image=2∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S007 · impliesBefore

source index=6∈Fin(8)

After

image=1∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S008 · impliesBefore

source index=7∈Fin(8)

After

image=0∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

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





S009 · impliesBefore

Fin(8)→Fin(8);S=[2, 3];full map=[7, 6, 5, 4, 3, 2, 1, 0]

After

principal(S)={A:S⊆A};empty generators allowed,no NeBot

Conditions: none

The declared convention allows empty S;its family of supersets then contains the empty set,and no proper-filter or NeBot condition is added.This is a finite principal-generator model,not a general sequence or point limit.

Step identifiers and dependenciesRule: finite_principal_generator_convention · Uses: G001, S008





S010 · impliesBefore

source index=0∈Fin(8)

After

image=7∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S009





S011 · impliesBefore

source index=1∈Fin(8)

After

image=6∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S010





S012 · impliesBefore

source index=2∈Fin(8)

After

image=5∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S011





S013 · impliesBefore

source index=3∈Fin(8)

After

image=4∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S012





S014 · impliesBefore

source index=4∈Fin(8)

After

image=3∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S013





S015 · impliesBefore

source index=5∈Fin(8)

After

image=2∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S014





S016 · impliesBefore

source index=6∈Fin(8)

After

image=1∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S015





S017 · impliesBefore

source index=7∈Fin(8)

After

image=0∈Fin(8)

Conditions: none

Every entry of the complete table must be legal;an entry being unused later does not waive total-map typing.

Step identifiers and dependenciesRule: complete_after_map_row · Uses: G001, S016





S018 · impliesBefore

x=2;f(x)=5

After

g(f(x))=2

Conditions: none

The first route composes at each source element,retaining the direction of both maps.

Step identifiers and dependenciesRule: principal_direct_composition_row · Uses: G001, S017





S019 · impliesBefore

x=3;f(x)=4

After

g(f(x))=3

Conditions: none

The first route composes at each source element,retaining the direction of both maps.

Step identifiers and dependenciesRule: principal_direct_composition_row · Uses: G001, S018





S020 · impliesBefore

distinct intermediate image=4

After

g(y)=3

Conditions: none

The second route deduplicates f(S) before applying g;a total function assigns the same successor to the same intermediate value,so deduplication loses no final image.

Step identifiers and dependenciesRule: principal_image_then_map_row · Uses: G001, S019





S021 · impliesBefore

distinct intermediate image=5

After

g(y)=2

Conditions: none

The second route deduplicates f(S) before applying g;a total function assigns the same successor to the same intermediate value,so deduplication loses no final image.

Step identifiers and dependenciesRule: principal_image_then_map_row · Uses: G001, S020





S022 · impliesBefore

direct composite image=[2, 3];image then map=[2, 3]

After

(g∘f)(S)=g(f(S)) in this complete finite model

Conditions: none

Both routes give the same final image;empty S gives empty images on both routes.No general analytic limit or additional nonemptiness premise is introduced.

Step identifiers and dependenciesRule: principal_composition_image_identity · Uses: G001, S021









## Reverse checks


- S022 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S021 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S020 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S019 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S018 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S017 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S016 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S015 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S014 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S013 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S012 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S011 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S010 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S009 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- 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

([2, 3], [2, 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: f566b2e889ac450fa4f19493421c357394f51eec7476ebc0571e548fa0640b88
- candidate record SHA-256: ccfe92d2f23e6cf7595fa8bbe7134c89eabcd1f388de009e2aadd4e80c5f1449
- semantic review receipt SHA-256: 71e7db519df31f3a164533e472e293cb64f001b475a8d002b4a5c2740a237b56
- question-first witness SHA-256: 5a43f4f81b6256281f8d139a4010bbde127be803c528e5878857269c8f854462
- Lean: NOT_RUN · human review: NOT_PERFORMED

[Same-source full JSON](https://ocme.evemisslab.com/data/question-derivations/questions/q-20261008-advance-20261011-r07-tends-to-relation-0088.json)




