Explore related knowledge and questions →

Question 21788: A Matching Composite Product Does Not Qualify as a Prime Factorization

On this page
  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

Return to catalogue page 109

← Question derivation index · Original question batch

R0042-21788 · q-20261014-advance-20261109-r06-mobius-function-0038

Original question and givens

Use positive integer n=82, supplied factors=[2, 41] in original order. Give (n, factors, valid_prime_product, mu_or_null, agrees_with_canonical, certificate).

  • G001 — Use positive integer n=82, supplied factors=[2, 41] in original order. Give (n, factors, valid_prime_product, mu_or_null, agrees_with_canonical, 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.

Step-by-step derivation

S001 · implies

Before

source operation=mobius-factorization-audit;original snapshot and mathematics retained

After

explicit ordered source output fields=[n, factors, valid_prime_product, mu_or_null, agrees_with_canonical, certificate]

Conditions: none

Keep the original historical interface marker while listing ordered source fields without JavaScript.Tags are not additional evidence;fixed No markers retain their source claim scope.

Step identifiers and dependencies

Rule: source_ordered_interface_explicit_without_javascript · Uses: G001

S002 · implies

Before

mobius ORIGINAL factor index0:ORIGINAL candidate factor=2;ALL possible trial divisors2..floor(sqrt(v))=[]

After

ALL [divisor,remainder] rows=[];prime=Yes

Conditions: none

A composite integer greater than1 has a divisor at most its square root.Complete nondivisibility over that interval certifies primality,including the empty interval for2.Matching a product cannot replace this obligation.

Step identifiers and dependencies

Rule: upf_every_trial_divisor_primality_not_product_only · Uses: G001, S001

S003 · calculation

Before

Mobius candidate exact full product at factor0 := mul(1, 2)

After

Mobius candidate exact full product at factor0 = 2

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · implies

Before

mobius ORIGINAL factor index1:ORIGINAL candidate factor=41;ALL possible trial divisors2..floor(sqrt(v))=[2, 3, 4, 5, 6]

After

ALL [divisor,remainder] rows=[[2, 1], [3, 2], [4, 1], [5, 1], [6, 5]];prime=Yes

Conditions: none

A composite integer greater than1 has a divisor at most its square root.Complete nondivisibility over that interval certifies primality,including the empty interval for2.Matching a product cannot replace this obligation.

Step identifiers and dependencies

Rule: upf_every_trial_divisor_primality_not_product_only · Uses: G001, S003

S005 · calculation

Before

Mobius candidate exact full product at factor1 := mul(2, 41)

After

Mobius candidate exact full product at factor1 = 82

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S004

S006 · implies

Before

mobius candidate canonical comparison:actual positive input for mu=82

After

complete prime multiplicities required for this input;mu(1) uses empty product,not a partial factor search

Conditions: none

Identify whether the input is the original n or one of its positive divisors.Every mu evaluation requires complete prime multiplicities,not a partial factor search.

Step identifiers and dependencies

Rule: mobius_complete_UPF_input_role · Uses: G001, S005

S007 · implies

Before

ORIGINAL positive integer absolute magnitude=82>1

After

initialize remaining=n,prime multiset empty;invariant product(extracted)*remaining=n;every smaller trial divisor has been exhausted

Conditions: none

Divide only by an actual divisor and exhaust smaller candidates,which justifies primality of each extracted divisor without assuming n is prime.

Step identifiers and dependencies

Rule: upf_factorization_remaining_product_invariant · Uses: G001, S006

S008 · calculation

Before

upf extract divisor2 occurrence0 := div(82, 2)

After

upf extract divisor2 occurrence0 = 41

Conditions: none

Substitute the original roles and established intermediates exactly,retaining order,signs and quantified conditions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · implies

Before

next divisor=2;previous remaining=82;all smaller divisors exhausted

After

extracted multiplicity=1;next remaining=41;remaining modulo2=1;extracted multiset=[2]

Conditions: none

Exhaust every multiplicity before advancing.The stopping test concerns the current remainder,and the final prime remainder must not be omitted.

Step identifiers and dependencies

Rule: upf_complete_trial_division_remaining_invariant · Uses: G001, S008

S010 · implies

Before

next divisor=3;previous remaining=41;all smaller divisors exhausted

After

extracted multiplicity=0;next remaining=41;remaining modulo3=2;extracted multiset=[2]

Conditions: none

Exhaust every multiplicity before advancing.The stopping test concerns the current remainder,and the final prime remainder must not be omitted.

Step identifiers and dependencies

Rule: upf_complete_trial_division_remaining_invariant · Uses: G001, S009

S011 · implies

Before

next divisor=4;previous remaining=41;all smaller divisors exhausted

After

extracted multiplicity=0;next remaining=41;remaining modulo4=1;extracted multiset=[2]

Conditions: none

Exhaust every multiplicity before advancing.The stopping test concerns the current remainder,and the final prime remainder must not be omitted.

Step identifiers and dependencies

Rule: upf_complete_trial_division_remaining_invariant · Uses: G001, S010

S012 · implies

Before

next divisor=5;previous remaining=41;all smaller divisors exhausted

After

extracted multiplicity=0;next remaining=41;remaining modulo5=1;extracted multiset=[2]

Conditions: none

Exhaust every multiplicity before advancing.The stopping test concerns the current remainder,and the final prime remainder must not be omitted.

Step identifiers and dependencies

Rule: upf_complete_trial_division_remaining_invariant · Uses: G001, S011

S013 · implies

Before

next divisor=6;previous remaining=41;all smaller divisors exhausted

After

extracted multiplicity=0;next remaining=41;remaining modulo6=5;extracted multiset=[2]

Conditions: none

Exhaust every multiplicity before advancing.The stopping test concerns the current remainder,and the final prime remainder must not be omitted.

Step identifiers and dependencies

Rule: upf_complete_trial_division_remaining_invariant · Uses: G001, S012

S014 · calculation

Before

upf canonical complete product factor0 := mul(1, 2)

After

upf canonical complete product factor0 = 2

Conditions: none

Substitute the original roles and established intermediates exactly,retaining order,signs and quantified conditions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S013

S015 · calculation

Before

upf canonical complete product factor1 := mul(2, 41)

After

upf canonical complete product factor1 = 82

Conditions: none

Substitute the original roles and established intermediates exactly,retaining order,signs and quantified conditions.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S014

S016 · implies

Before

exhausted trial divisors below7;terminal remaining=41;d*d>remaining;ORIGINAL n=82

After

complete increasing prime multiset=[2, 41];full product=82;a composite terminal remainder would have an already tested smaller divisor

Conditions: none

If a terminal remainder greater than1 were composite,its least prime factor would already have been exhausted,a contradiction.The final entry is therefore prime.This certifies this instance;general existence follows by strong induction,recursively splitting a composite into smaller positive factors.

Step identifiers and dependencies

Rule: upf_final_prime_remainder_complete_existence_instance · Uses: G001, S015

S017 · implies

Before

mobius candidate canonical comparison:input=82;COMPLETE prime multiset=[2, 41];distinct primes=[2, 41]

After

mu=1;empty product case=No;repeated prime=No

Conditions: none

The empty prime multiset for1 gives mu1=1.A repeated prime gives a square divisor and value0;otherwise distinct-prime parity determines the sign.Sorting must not discard multiplicities.

Step identifiers and dependencies

Rule: mobius_value_one_repeated_prime_or_squarefree_parity · Uses: G001, S016

S018 · implies

Before

ORIGINAL n=82;ORIGINAL factor order=[2, 41];ALL primality flags=[Yes, Yes];EXACT full product=82

After

valid prime product=Yes;candidate mu_or_null=1;canonical mu=1;agreement=Yes;large product is NOT a rounded Number output field

Conditions: none

Compute mu from a candidate only after primality and full-product equality qualify.Matching composite products or incomplete prime lists give null.This interface does not project the product as Number;do not import the unrelated UPF unsafe-output rejection.

Step identifiers and dependencies

Rule: mobius_candidate_prime_product_before_value_no_rounded_projection · Uses: G001, S017

Reverse checks

  • 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 — Recompute upf canonical complete product factor1 with exact rational arithmetic, not rounded decimals.
  • S014 · premise_and_result_audit — Recompute upf canonical complete product factor0 with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute upf extract divisor2 occurrence0 with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute Mobius candidate exact full product at factor1 with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute Mobius candidate exact full product at factor0 with exact rational arithmetic, not rounded decimals.
  • 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

(82, [2, 41], Yes, 1, Yes, complete_UPF_multiplicity_and_distinct_prime_count)

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: 2e89e0ed9d9fa060d0ededd6e2d5d5d3b90c20ccaefc6b46b48375e912442a6b
  • candidate record SHA-256: 40a5b167bbbef4ea8ce7bf90b1ff7cb5eb8243aba23a2e5fe45a95455f7df58f
  • semantic review receipt SHA-256: dd44555041dfbb6fe9936aa00b9a5f8c5982c2784ef61dd0cbd5d1a303a49c1a
  • question-first witness SHA-256: 9a6011263f6ac53b9a1fd57addf2f3e2f6088b54802c539f332d689480dc2d17
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON