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Question 21097: A Whole Nondecreasing Bounded Tail Has Its Supremum as Limit

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

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R0041-21097 · q-20261014-advance-20261108-r02-monotone-sequence-convergence-theorem-0022

Original question and givens

Use the whole real sequence a_n=L−c/(n+shift) for every n≥0, with L=22/23, positive c=22 and positive integer shift=2. The denominator shift is distinct from the theorem's supremum/infimum bound. The entire symbolic family, not a displayed finite prefix, supplies monotonicity and the corresponding bound. Give (direction, limit, coefficient, shift, first_three_terms, symbolic_certificate, certificate).

  • G001 — Use the whole real sequence a_n=L−c/(n+shift) for every n≥0, with L=22/23, positive c=22 and positive integer shift=2. The denominator shift is distinct from the theorem's supremum/infimum bound. The entire symbolic family, not a displayed finite prefix, supplies monotonicity and the corresponding bound. Give (direction, limit, coefficient, shift, first_three_terms, symbolic_certificate, 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=monoseq-increasing-limit-certificate;original snapshot and mathematics retained

After

explicit ordered source output fields=[direction, limit, coefficient, shift, first_three_terms, symbolic_certificate, certificate]

Conditions: none

Retain the historical interface marker while listing ordered output fields without JavaScript.Fields and tags are not extra mathematical evidence;fixed No markers retain their claim scope.

Step identifiers and dependencies

Rule: source_ordered_interface_explicit_without_javascript · Uses: G001

S002 · implies

Before

ORIGINAL direction=increasing,L=22/23,c=22>0,shift=2>=1;WHOLE a_n=L+(-1)c/(n+shift) for ALL n>=0

After

for EVERY n>=0,a_(n+1)-a_n=(1)*(22)/((n+2)*(n+1+2));positive denominator;all a_n strictly below L=22/23

Conditions: none

Subtract adjacent symbolic terms using a common denominator.Positivity fixes the sign and gives upper bound L in the increasing case or lower bound L in the decreasing case.This holds for all n,allows negative L,and is not a three-term sample proof.

Step identifiers and dependencies

Rule: monoseq_whole_symbolic_monotonicity_and_matching_bound · Uses: G001, S001

S003 · implies

Before

WHOLE increasing law with ORIGINAL L=22/23,c=22,shift=2

After

for ANY epsilon>0 choose natural N with N+2>22/epsilon;ALL n>=N have |a_n-L|<epsilon;L is supremum but NOT attained because c/(n+shift)>0

Conditions: none

The Archimedean choice controls every later term.Any smaller upper bound or larger lower bound is broken by a term sufficiently close to L,so L is the sup/inf.In the general monotone theorem,sup−epsilon is not an upper bound,which supplies a term;monotonicity then traps the tail.The decreasing proof is dual.

Step identifiers and dependencies

Rule: monoseq_sup_inf_limit_proof_and_nonattainment · Uses: G001, S002

S004 · calculation

Before

monoseq illustrative source n=0 denominator := sum(0, 2)

After

monoseq illustrative source n=0 denominator = 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, S003

S005 · calculation

Before

monoseq illustrative source n=0 unsigned tail := div(22, 2)

After

monoseq illustrative source n=0 unsigned tail = 11

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, S004

S006 · calculation

Before

monoseq illustrative source n=0 signed value := sub(22/23, 11)

After

monoseq illustrative source n=0 signed value = -231/23

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, S005

S007 · calculation

Before

monoseq illustrative source n=1 denominator := sum(1, 2)

After

monoseq illustrative source n=1 denominator = 3

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, S006

S008 · calculation

Before

monoseq illustrative source n=1 unsigned tail := div(22, 3)

After

monoseq illustrative source n=1 unsigned tail = 22/3

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 · calculation

Before

monoseq illustrative source n=1 signed value := sub(22/23, 22/3)

After

monoseq illustrative source n=1 signed value = -440/69

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, S008

S010 · calculation

Before

monoseq illustrative source n=2 denominator := sum(2, 2)

After

monoseq illustrative source n=2 denominator = 4

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, S009

S011 · calculation

Before

monoseq illustrative source n=2 unsigned tail := div(22, 4)

After

monoseq illustrative source n=2 unsigned tail = 11/2

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, S010

S012 · calculation

Before

monoseq illustrative source n=2 signed value := sub(22/23, 11/2)

After

monoseq illustrative source n=2 signed value = -209/46

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, S011

Reverse checks

  • S012 · premise_and_result_audit — Recompute monoseq illustrative source n=2 signed value with exact rational arithmetic, not rounded decimals.
  • S011 · premise_and_result_audit — Recompute monoseq illustrative source n=2 unsigned tail with exact rational arithmetic, not rounded decimals.
  • S010 · premise_and_result_audit — Recompute monoseq illustrative source n=2 denominator with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Recompute monoseq illustrative source n=1 signed value with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Recompute monoseq illustrative source n=1 unsigned tail with exact rational arithmetic, not rounded decimals.
  • S007 · premise_and_result_audit — Recompute monoseq illustrative source n=1 denominator with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Recompute monoseq illustrative source n=0 signed value with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Recompute monoseq illustrative source n=0 unsigned tail with exact rational arithmetic, not rounded decimals.
  • S004 · premise_and_result_audit — Recompute monoseq illustrative source n=0 denominator 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

(increasing, 22/23, 22, 2, [-231/23, -440/69, -209/46], Yes, nondecreasing_bounded_above_supremum_limit)

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: 536465f74e387a2720a9514dcf7cbc234ada37c2cd9fb418ad76e88a82cf75f4
  • candidate record SHA-256: cb5a38ba4e1dc14ad3550c51dac6df526c18ec9c346071a172418fa3724b8a35
  • semantic review receipt SHA-256: 8f134403487694af4c70d2e00ec84bab542043ef4b3c54517c04f3c409c0262a
  • question-first witness SHA-256: ad772845088ed8e99f87f90d4264b05ea97be35775305a02011af5ee35f0f4ce
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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