# Question 24064: A Declared Shifted Polynomial Reconstructs Exactly from Its Finite Jet

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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.

R0047-24064 · q-20261014-advance-20261112-r02-taylor-polynomial-0064



## Original question and givens

Use shifted_coefficients=[14, 28, 42, 56] of the explicit polynomial sum c_k*(x−a)^k, center a=1, evaluation point=2. Give (shifted_coefficients, derivatives_at_center, reconstructed_coefficients, point, original_value, reconstructed_value, equal, certificate).


- G001 — Use shifted_coefficients=[14, 28, 42, 56] of the explicit polynomial sum c_k*(x−a)^k, center a=1, evaluation point=2. Give (shifted_coefficients, derivatives_at_center, reconstructed_coefficients, point, original_value, reconstructed_value, equal, certificate).





## 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-taylor-polynomial](https://ocme.evemisslab.com/en/mko/mko-taylor-polynomial/)





## Step-by-step derivation

S001 · impliesBefore

source roles = [taylor-exact-polynomial-reconstruction]

After

derived = [[shifted_coefficients, derivatives_at_center, reconstructed_coefficients, point, original_value, reconstructed_value, equal, certificate]]

Conditions: none

List the source field order without JavaScript.Gradient boundary uses its original mode to choose6,8 or7 fields;no padding or answer-derived mode.

Step identifiers and dependenciesRule: source_ordered_fields_without_JS · Uses: G001





S002 · impliesBefore

source roles = [1, [14, 28, 42, 56]]

After

derived = [P(x)=sum c_k*(x-center)^k, 3]

Conditions: none

The whole finite polynomial is declared.At a,only its degree-k shifted monomial contributes k!*c_k to the kth derivative.This is not an infinite expansion of an arbitrary smooth function.

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





S003 · impliesBefore

source roles = [0]

After

derived = [1]

Conditions: none

The empty product0! is1,not0.

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





S004 · calculationBefore

Taylor derivative0 from shifted coefficient := mul(14, 1)

After

Taylor derivative0 from shifted coefficient = 14

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S005 · calculationBefore

Taylor recover coefficient0 := div(14, 1)

After

Taylor recover coefficient0 = 14

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S006 · calculationBefore

Taylor k1 factorial step1 := mul(1, 1)

After

Taylor k1 factorial step1 = 1

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S007 · calculationBefore

Taylor derivative1 from shifted coefficient := mul(28, 1)

After

Taylor derivative1 from shifted coefficient = 28

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S008 · calculationBefore

Taylor recover coefficient1 := div(28, 1)

After

Taylor recover coefficient1 = 28

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S009 · calculationBefore

Taylor k2 factorial step1 := mul(1, 1)

After

Taylor k2 factorial step1 = 1

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S010 · calculationBefore

Taylor k2 factorial step2 := mul(1, 2)

After

Taylor k2 factorial step2 = 2

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S011 · calculationBefore

Taylor derivative2 from shifted coefficient := mul(42, 2)

After

Taylor derivative2 from shifted coefficient = 84

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S012 · calculationBefore

Taylor recover coefficient2 := div(84, 2)

After

Taylor recover coefficient2 = 42

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S013 · calculationBefore

Taylor k3 factorial step1 := mul(1, 1)

After

Taylor k3 factorial step1 = 1

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S014 · calculationBefore

Taylor k3 factorial step2 := mul(1, 2)

After

Taylor k3 factorial step2 = 2

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S015 · calculationBefore

Taylor k3 factorial step3 := mul(2, 3)

After

Taylor k3 factorial step3 = 6

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S016 · calculationBefore

Taylor derivative3 from shifted coefficient := mul(56, 6)

After

Taylor derivative3 from shifted coefficient = 336

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S017 · calculationBefore

Taylor recover coefficient3 := div(336, 6)

After

Taylor recover coefficient3 = 56

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S018 · calculationBefore

Taylor SAME point minus declared center := sub(2, 1)

After

Taylor SAME point minus declared center = 1

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S019 · calculationBefore

Taylor original Horner product3 := mul(0, 1)

After

Taylor original Horner product3 = 0

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S020 · calculationBefore

Taylor original Horner sum3 := sum(0, 56)

After

Taylor original Horner sum3 = 56

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S021 · calculationBefore

Taylor original Horner product2 := mul(56, 1)

After

Taylor original Horner product2 = 56

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S022 · calculationBefore

Taylor original Horner sum2 := sum(56, 42)

After

Taylor original Horner sum2 = 98

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

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





S023 · calculationBefore

Taylor original Horner product1 := mul(98, 1)

After

Taylor original Horner product1 = 98

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S022





S024 · calculationBefore

Taylor original Horner sum1 := sum(98, 28)

After

Taylor original Horner sum1 = 126

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S023





S025 · calculationBefore

Taylor original Horner product0 := mul(126, 1)

After

Taylor original Horner product0 = 126

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S024





S026 · calculationBefore

Taylor original Horner sum0 := sum(126, 14)

After

Taylor original Horner sum0 = 140

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S025





S027 · calculationBefore

Taylor reconstructed Horner product3 := mul(0, 1)

After

Taylor reconstructed Horner product3 = 0

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S026





S028 · calculationBefore

Taylor reconstructed Horner sum3 := sum(0, 56)

After

Taylor reconstructed Horner sum3 = 56

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S027





S029 · calculationBefore

Taylor reconstructed Horner product2 := mul(56, 1)

After

Taylor reconstructed Horner product2 = 56

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S028





S030 · calculationBefore

Taylor reconstructed Horner sum2 := sum(56, 42)

After

Taylor reconstructed Horner sum2 = 98

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S029





S031 · calculationBefore

Taylor reconstructed Horner product1 := mul(98, 1)

After

Taylor reconstructed Horner product1 = 98

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S030





S032 · calculationBefore

Taylor reconstructed Horner sum1 := sum(98, 28)

After

Taylor reconstructed Horner sum1 = 126

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S031





S033 · calculationBefore

Taylor reconstructed Horner product0 := mul(126, 1)

After

Taylor reconstructed Horner product0 = 126

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S032





S034 · calculationBefore

Taylor reconstructed Horner sum0 := sum(126, 14)

After

Taylor reconstructed Horner sum0 = 140

Conditions: none

Substitute original roles and established intermediates exactly;check nonzero denominators and do not round.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S033





S035 · impliesBefore

source roles = [[14, 28, 42, 56], [14, 28, 42, 56], 1, 2]

After

derived = [Yes, 140, 140, Yes]

Conditions: none

Recover every coefficient first to identify the whole polynomial,then evaluate at the same point and center.One coincident point value alone would not establish polynomial identity.

Step identifiers and dependenciesRule: Taylor_ALL_coefficients_recovered_before_point_equality · Uses: G001, S034









## Reverse checks


- S035 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S034 · premise_and_result_audit — Recompute Taylor reconstructed Horner sum0 with exact rational arithmetic, not rounded decimals.
- S033 · premise_and_result_audit — Recompute Taylor reconstructed Horner product0 with exact rational arithmetic, not rounded decimals.
- S032 · premise_and_result_audit — Recompute Taylor reconstructed Horner sum1 with exact rational arithmetic, not rounded decimals.
- S031 · premise_and_result_audit — Recompute Taylor reconstructed Horner product1 with exact rational arithmetic, not rounded decimals.
- S030 · premise_and_result_audit — Recompute Taylor reconstructed Horner sum2 with exact rational arithmetic, not rounded decimals.
- S029 · premise_and_result_audit — Recompute Taylor reconstructed Horner product2 with exact rational arithmetic, not rounded decimals.
- S028 · premise_and_result_audit — Recompute Taylor reconstructed Horner sum3 with exact rational arithmetic, not rounded decimals.
- S027 · premise_and_result_audit — Recompute Taylor reconstructed Horner product3 with exact rational arithmetic, not rounded decimals.
- S026 · premise_and_result_audit — Recompute Taylor original Horner sum0 with exact rational arithmetic, not rounded decimals.
- S025 · premise_and_result_audit — Recompute Taylor original Horner product0 with exact rational arithmetic, not rounded decimals.
- S024 · premise_and_result_audit — Recompute Taylor original Horner sum1 with exact rational arithmetic, not rounded decimals.
- S023 · premise_and_result_audit — Recompute Taylor original Horner product1 with exact rational arithmetic, not rounded decimals.
- S022 · premise_and_result_audit — Recompute Taylor original Horner sum2 with exact rational arithmetic, not rounded decimals.
- S021 · premise_and_result_audit — Recompute Taylor original Horner product2 with exact rational arithmetic, not rounded decimals.
- S020 · premise_and_result_audit — Recompute Taylor original Horner sum3 with exact rational arithmetic, not rounded decimals.
- S019 · premise_and_result_audit — Recompute Taylor original Horner product3 with exact rational arithmetic, not rounded decimals.
- S018 · premise_and_result_audit — Recompute Taylor SAME point minus declared center with exact rational arithmetic, not rounded decimals.
- S017 · premise_and_result_audit — Recompute Taylor recover coefficient3 with exact rational arithmetic, not rounded decimals.
- S016 · premise_and_result_audit — Recompute Taylor derivative3 from shifted coefficient with exact rational arithmetic, not rounded decimals.
- S015 · premise_and_result_audit — Recompute Taylor k3 factorial step3 with exact rational arithmetic, not rounded decimals.
- S014 · premise_and_result_audit — Recompute Taylor k3 factorial step2 with exact rational arithmetic, not rounded decimals.
- S013 · premise_and_result_audit — Recompute Taylor k3 factorial step1 with exact rational arithmetic, not rounded decimals.
- S012 · premise_and_result_audit — Recompute Taylor recover coefficient2 with exact rational arithmetic, not rounded decimals.
- S011 · premise_and_result_audit — Recompute Taylor derivative2 from shifted coefficient with exact rational arithmetic, not rounded decimals.
- S010 · premise_and_result_audit — Recompute Taylor k2 factorial step2 with exact rational arithmetic, not rounded decimals.
- S009 · premise_and_result_audit — Recompute Taylor k2 factorial step1 with exact rational arithmetic, not rounded decimals.
- S008 · premise_and_result_audit — Recompute Taylor recover coefficient1 with exact rational arithmetic, not rounded decimals.
- S007 · premise_and_result_audit — Recompute Taylor derivative1 from shifted coefficient with exact rational arithmetic, not rounded decimals.
- S006 · premise_and_result_audit — Recompute Taylor k1 factorial step1 with exact rational arithmetic, not rounded decimals.
- S005 · premise_and_result_audit — Recompute Taylor recover coefficient0 with exact rational arithmetic, not rounded decimals.
- S004 · premise_and_result_audit — Recompute Taylor derivative0 from shifted coefficient with exact rational arithmetic, not rounded decimals.
- 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

([14, 28, 42, 56], [14, 28, 84, 336], [14, 28, 42, 56], 2, 140, 140, Yes, degree_at_most_n_polynomial_is_exactly_reconstructed)

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: 94df77c9f7aebbb48f7453881db998aa643a3fd453147188983c731553813889
- candidate record SHA-256: bdf3431dc1b9a6a195b84d032a6a49f11995b3c601fe85c5452378b323ee4c80
- semantic review receipt SHA-256: 9b43b9823e9bd2478d6caa5b57ffed161c2c8956af86974e901d5662ad994386
- question-first witness SHA-256: eb97596068e2d5648033bab2b8f6ca9b653bbe8cb77c0f8e1d16d0c40e46f50b
- Lean: NOT_RUN · human review: NOT_PERFORMED

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