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Question 22544: A Complete Initial State Gives a Unique Forward Prefix

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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R0044-22544 · q-20261014-advance-20261110-r05-recurrence-relation-0069

Original question and givens

Use order r=2, coefficients=[1, 2] in oldest-to-newest order, constant=1 and initial_values=[18, 19], where initial_values[j]=a_j. For n≥r, a_n=constant+sum over j=0..r−1 of coefficients[j]*a_(n−r+j). The state shifts left then appends the new scalar. All intermediate integer operations must be safe. Target index=7. Give (order, initial_count, target_n, target_value, unique_prefix, certificate).

  • G001 — Use order r=2, coefficients=[1, 2] in oldest-to-newest order, constant=1 and initial_values=[18, 19], where initial_values[j]=a_j. For n≥r, a_n=constant+sum over j=0..r−1 of coefficients[j]*a_(n−r+j). The state shifts left then appends the new scalar. All intermediate integer operations must be safe. Target index=7. Give (order, initial_count, target_n, target_value, unique_prefix, 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=recurrence-initial-value-uniqueness;original snapshot and mathematics retained

After

explicit ordered source output fields=[order, initial_count, target_n, target_value, unique_prefix, certificate]

Conditions: none

Keep the historical interface marker and list ordered source fields without JavaScript.Tags are not additional evidence;fixed No markers retain their scope.The ordering helper supplies protocol order,not mathematical correctness.

Step identifiers and dependencies

Rule: source_ordered_interface_explicit_without_javascript · Uses: G001

S002 · implies

Before

recurrence ORIGINAL:ORIGINAL order=2;oldest-to-newest coefficients=[1, 2];constant=1;ALL initial a_0..a_(r-1)=[18, 19]

After

for EVERY n>=2,a_n=constant+sum_j coefficients[j]*a_(n-r+j);current prefix length=2;forward rule is total and single-valued

Conditions: none

Fix all r initials and the oldest-to-newest coefficient roles.Given the preceding r values,the next value is uniquely determined.This is a forward definition,not a closed form or convergence claim.

Step identifiers and dependencies

Rule: recurrence_complete_initial_state_and_total_single_value_rule · Uses: G001, S001

S003 · calculation

Before

recurrence ORIGINAL n=2 ORIGINAL coefficient0 times a_0 := mul(1, 18)

After

recurrence ORIGINAL n=2 ORIGINAL coefficient0 times a_0 = 18

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · calculation

Before

recurrence ORIGINAL n=2 partial sum after coefficient0 := sum(1, 18)

After

recurrence ORIGINAL n=2 partial sum after coefficient0 = 19

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · calculation

Before

recurrence ORIGINAL n=2 ORIGINAL coefficient1 times a_1 := mul(2, 19)

After

recurrence ORIGINAL n=2 ORIGINAL coefficient1 times a_1 = 38

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S004

S006 · calculation

Before

recurrence ORIGINAL n=2 partial sum after coefficient1 := sum(19, 38)

After

recurrence ORIGINAL n=2 partial sum after coefficient1 = 57

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · implies

Before

recurrence ORIGINAL:ORIGINAL target n=2;previous state a_(n-r)..a_(n-1)=[18, 19];ALL [j,source_index,coefficient,value,product] rows=[[0, 0, 1, 18, 18], [1, 1, 2, 19, 38]]

After

new a_2=57;next state=[19, 57];drop ONLY oldest state entry then append new scalar;prefix now=[18, 19, 57]

Conditions: none

Multiply each coefficient by its specified original index,add to the constant and check the source safe-integer range.Shift left and append the new scalar;do not reverse coefficients or feed the appended value back into this same update.

Step identifiers and dependencies

Rule: recurrence_EVERY_state_update_shift_left_append_exact · Uses: G001, S006

S008 · calculation

Before

recurrence ORIGINAL n=3 ORIGINAL coefficient0 times a_1 := mul(1, 19)

After

recurrence ORIGINAL n=3 ORIGINAL coefficient0 times a_1 = 19

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · calculation

Before

recurrence ORIGINAL n=3 partial sum after coefficient0 := sum(1, 19)

After

recurrence ORIGINAL n=3 partial sum after coefficient0 = 20

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · calculation

Before

recurrence ORIGINAL n=3 ORIGINAL coefficient1 times a_2 := mul(2, 57)

After

recurrence ORIGINAL n=3 ORIGINAL coefficient1 times a_2 = 114

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S009

S011 · calculation

Before

recurrence ORIGINAL n=3 partial sum after coefficient1 := sum(20, 114)

After

recurrence ORIGINAL n=3 partial sum after coefficient1 = 134

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S010

S012 · implies

Before

recurrence ORIGINAL:ORIGINAL target n=3;previous state a_(n-r)..a_(n-1)=[19, 57];ALL [j,source_index,coefficient,value,product] rows=[[0, 1, 1, 19, 19], [1, 2, 2, 57, 114]]

After

new a_3=134;next state=[57, 134];drop ONLY oldest state entry then append new scalar;prefix now=[18, 19, 57, 134]

Conditions: none

Multiply each coefficient by its specified original index,add to the constant and check the source safe-integer range.Shift left and append the new scalar;do not reverse coefficients or feed the appended value back into this same update.

Step identifiers and dependencies

Rule: recurrence_EVERY_state_update_shift_left_append_exact · Uses: G001, S011

S013 · calculation

Before

recurrence ORIGINAL n=4 ORIGINAL coefficient0 times a_2 := mul(1, 57)

After

recurrence ORIGINAL n=4 ORIGINAL coefficient0 times a_2 = 57

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S012

S014 · calculation

Before

recurrence ORIGINAL n=4 partial sum after coefficient0 := sum(1, 57)

After

recurrence ORIGINAL n=4 partial sum after coefficient0 = 58

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S013

S015 · calculation

Before

recurrence ORIGINAL n=4 ORIGINAL coefficient1 times a_3 := mul(2, 134)

After

recurrence ORIGINAL n=4 ORIGINAL coefficient1 times a_3 = 268

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S014

S016 · calculation

Before

recurrence ORIGINAL n=4 partial sum after coefficient1 := sum(58, 268)

After

recurrence ORIGINAL n=4 partial sum after coefficient1 = 326

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S015

S017 · implies

Before

recurrence ORIGINAL:ORIGINAL target n=4;previous state a_(n-r)..a_(n-1)=[57, 134];ALL [j,source_index,coefficient,value,product] rows=[[0, 2, 1, 57, 57], [1, 3, 2, 134, 268]]

After

new a_4=326;next state=[134, 326];drop ONLY oldest state entry then append new scalar;prefix now=[18, 19, 57, 134, 326]

Conditions: none

Multiply each coefficient by its specified original index,add to the constant and check the source safe-integer range.Shift left and append the new scalar;do not reverse coefficients or feed the appended value back into this same update.

Step identifiers and dependencies

Rule: recurrence_EVERY_state_update_shift_left_append_exact · Uses: G001, S016

S018 · calculation

Before

recurrence ORIGINAL n=5 ORIGINAL coefficient0 times a_3 := mul(1, 134)

After

recurrence ORIGINAL n=5 ORIGINAL coefficient0 times a_3 = 134

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S017

S019 · calculation

Before

recurrence ORIGINAL n=5 partial sum after coefficient0 := sum(1, 134)

After

recurrence ORIGINAL n=5 partial sum after coefficient0 = 135

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S018

S020 · calculation

Before

recurrence ORIGINAL n=5 ORIGINAL coefficient1 times a_4 := mul(2, 326)

After

recurrence ORIGINAL n=5 ORIGINAL coefficient1 times a_4 = 652

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S019

S021 · calculation

Before

recurrence ORIGINAL n=5 partial sum after coefficient1 := sum(135, 652)

After

recurrence ORIGINAL n=5 partial sum after coefficient1 = 787

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S020

S022 · implies

Before

recurrence ORIGINAL:ORIGINAL target n=5;previous state a_(n-r)..a_(n-1)=[134, 326];ALL [j,source_index,coefficient,value,product] rows=[[0, 3, 1, 134, 134], [1, 4, 2, 326, 652]]

After

new a_5=787;next state=[326, 787];drop ONLY oldest state entry then append new scalar;prefix now=[18, 19, 57, 134, 326, 787]

Conditions: none

Multiply each coefficient by its specified original index,add to the constant and check the source safe-integer range.Shift left and append the new scalar;do not reverse coefficients or feed the appended value back into this same update.

Step identifiers and dependencies

Rule: recurrence_EVERY_state_update_shift_left_append_exact · Uses: G001, S021

S023 · calculation

Before

recurrence ORIGINAL n=6 ORIGINAL coefficient0 times a_4 := mul(1, 326)

After

recurrence ORIGINAL n=6 ORIGINAL coefficient0 times a_4 = 326

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S022

S024 · calculation

Before

recurrence ORIGINAL n=6 partial sum after coefficient0 := sum(1, 326)

After

recurrence ORIGINAL n=6 partial sum after coefficient0 = 327

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S023

S025 · calculation

Before

recurrence ORIGINAL n=6 ORIGINAL coefficient1 times a_5 := mul(2, 787)

After

recurrence ORIGINAL n=6 ORIGINAL coefficient1 times a_5 = 1574

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S024

S026 · calculation

Before

recurrence ORIGINAL n=6 partial sum after coefficient1 := sum(327, 1574)

After

recurrence ORIGINAL n=6 partial sum after coefficient1 = 1901

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S025

S027 · implies

Before

recurrence ORIGINAL:ORIGINAL target n=6;previous state a_(n-r)..a_(n-1)=[326, 787];ALL [j,source_index,coefficient,value,product] rows=[[0, 4, 1, 326, 326], [1, 5, 2, 787, 1574]]

After

new a_6=1901;next state=[787, 1901];drop ONLY oldest state entry then append new scalar;prefix now=[18, 19, 57, 134, 326, 787, 1901]

Conditions: none

Multiply each coefficient by its specified original index,add to the constant and check the source safe-integer range.Shift left and append the new scalar;do not reverse coefficients or feed the appended value back into this same update.

Step identifiers and dependencies

Rule: recurrence_EVERY_state_update_shift_left_append_exact · Uses: G001, S026

S028 · calculation

Before

recurrence ORIGINAL n=7 ORIGINAL coefficient0 times a_5 := mul(1, 787)

After

recurrence ORIGINAL n=7 ORIGINAL coefficient0 times a_5 = 787

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S027

S029 · calculation

Before

recurrence ORIGINAL n=7 partial sum after coefficient0 := sum(1, 787)

After

recurrence ORIGINAL n=7 partial sum after coefficient0 = 788

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S028

S030 · calculation

Before

recurrence ORIGINAL n=7 ORIGINAL coefficient1 times a_6 := mul(2, 1901)

After

recurrence ORIGINAL n=7 ORIGINAL coefficient1 times a_6 = 3802

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S029

S031 · calculation

Before

recurrence ORIGINAL n=7 partial sum after coefficient1 := sum(788, 3802)

After

recurrence ORIGINAL n=7 partial sum after coefficient1 = 4590

Conditions: none

Substitute original roles,indices and established intermediates exactly,not floating-point approximations or another question's data.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S030

S032 · implies

Before

recurrence ORIGINAL:ORIGINAL target n=7;previous state a_(n-r)..a_(n-1)=[787, 1901];ALL [j,source_index,coefficient,value,product] rows=[[0, 5, 1, 787, 787], [1, 6, 2, 1901, 3802]]

After

new a_7=4590;next state=[1901, 4590];drop ONLY oldest state entry then append new scalar;prefix now=[18, 19, 57, 134, 326, 787, 1901, 4590]

Conditions: none

Multiply each coefficient by its specified original index,add to the constant and check the source safe-integer range.Shift left and append the new scalar;do not reverse coefficients or feed the appended value back into this same update.

Step identifiers and dependencies

Rule: recurrence_EVERY_state_update_shift_left_append_exact · Uses: G001, S031

S033 · implies

Before

recurrence ORIGINAL:complete ORIGINAL initial state=[18, 19];actual generated prefix=[18, 19, 57, 134, 326, 787, 1901, 4590]

After

ANY two sequences with SAME r initials and SAME total rule agree at n=2 by substitution,then at every later n by induction;this determines the requested prefix only

Conditions: none

Induct from equality of all r initials:the same single-valued rule gives equality of the next term,and hence every later prefix term.Finite generation proves no closed form,asymptotic behavior or analyticity.

Step identifiers and dependencies

Rule: recurrence_forward_uniqueness_induction_not_analytic_claim · Uses: G001, S032

Reverse checks

  • S033 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S032 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S031 · premise_and_result_audit — Recompute recurrence ORIGINAL n=7 partial sum after coefficient1 with exact rational arithmetic, not rounded decimals.
  • S030 · premise_and_result_audit — Recompute recurrence ORIGINAL n=7 ORIGINAL coefficient1 times a_6 with exact rational arithmetic, not rounded decimals.
  • S029 · premise_and_result_audit — Recompute recurrence ORIGINAL n=7 partial sum after coefficient0 with exact rational arithmetic, not rounded decimals.
  • S028 · premise_and_result_audit — Recompute recurrence ORIGINAL n=7 ORIGINAL coefficient0 times a_5 with exact rational arithmetic, not rounded decimals.
  • S027 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S026 · premise_and_result_audit — Recompute recurrence ORIGINAL n=6 partial sum after coefficient1 with exact rational arithmetic, not rounded decimals.
  • S025 · premise_and_result_audit — Recompute recurrence ORIGINAL n=6 ORIGINAL coefficient1 times a_5 with exact rational arithmetic, not rounded decimals.
  • S024 · premise_and_result_audit — Recompute recurrence ORIGINAL n=6 partial sum after coefficient0 with exact rational arithmetic, not rounded decimals.
  • S023 · premise_and_result_audit — Recompute recurrence ORIGINAL n=6 ORIGINAL coefficient0 times a_4 with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute recurrence ORIGINAL n=5 partial sum after coefficient1 with exact rational arithmetic, not rounded decimals.
  • S020 · premise_and_result_audit — Recompute recurrence ORIGINAL n=5 ORIGINAL coefficient1 times a_4 with exact rational arithmetic, not rounded decimals.
  • S019 · premise_and_result_audit — Recompute recurrence ORIGINAL n=5 partial sum after coefficient0 with exact rational arithmetic, not rounded decimals.
  • S018 · premise_and_result_audit — Recompute recurrence ORIGINAL n=5 ORIGINAL coefficient0 times a_3 with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute recurrence ORIGINAL n=4 partial sum after coefficient1 with exact rational arithmetic, not rounded decimals.
  • S015 · premise_and_result_audit — Recompute recurrence ORIGINAL n=4 ORIGINAL coefficient1 times a_3 with exact rational arithmetic, not rounded decimals.
  • S014 · premise_and_result_audit — Recompute recurrence ORIGINAL n=4 partial sum after coefficient0 with exact rational arithmetic, not rounded decimals.
  • S013 · premise_and_result_audit — Recompute recurrence ORIGINAL n=4 ORIGINAL coefficient0 times a_2 with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute recurrence ORIGINAL n=3 partial sum after coefficient1 with exact rational arithmetic, not rounded decimals.
  • S010 · premise_and_result_audit — Recompute recurrence ORIGINAL n=3 ORIGINAL coefficient1 times a_2 with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Recompute recurrence ORIGINAL n=3 partial sum after coefficient0 with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Recompute recurrence ORIGINAL n=3 ORIGINAL coefficient0 times a_1 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 — Recompute recurrence ORIGINAL n=2 partial sum after coefficient1 with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Recompute recurrence ORIGINAL n=2 ORIGINAL coefficient1 times a_1 with exact rational arithmetic, not rounded decimals.
  • S004 · premise_and_result_audit — Recompute recurrence ORIGINAL n=2 partial sum after coefficient0 with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Recompute recurrence ORIGINAL n=2 ORIGINAL coefficient0 times a_0 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

(2, 2, 7, 4590, Yes, total_single_valued_rule_plus_all_order_many_initial_values_gives_unique_prefix)

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.

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  • input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
  • original question SHA-256: fcc5dd5dbb75e44fe0c9f6bb298815b307716ba49756fb8ad92c0a0fb39df062
  • candidate record SHA-256: 350938629a79ee777112e5103b0df92653982ee64f389fbdadf40ea514a704fe
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