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Question 24638: Support Coverage Is Separate from Accidental Equality at One Point On this page Original question and givens Definition and scope Step-by-step derivation Reverse checks Result This question review and source binding Return to catalogue page 124
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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.
R0048-24638 · q-20261015-advance-20261113-r03-analytic-ordinary-generating-function-0038
Original question and givens Use finite_support_coefficients=[13, 26, 39] in increasing index order and the complete law a_n=0 after the list. Canonical answers trim trailing zero coefficients, without changing the original shared parameters. This is a complete finite-support law, not an unknown sequence observed only through a prefix. Use x=1/2, cutoff=2. Give (finite_support_coefficients, x, cutoff, term_rows, finite_sum, complete_support_included, certificate).
G001 — Use finite_support_coefficients=[13, 26, 39] in increasing index order and the complete law a_n=0 after the list. Canonical answers trim trailing zero coefficients, without changing the original shared parameters. This is a complete finite-support law, not an unknown sequence observed only through a prefix. Use x=1/2, cutoff=2. Give (finite_support_coefficients, x, cutoff, term_rows, finite_sum, complete_support_included, 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 roles = [ogf-finite-partial-sum] After
derived = [[finite_support_coefficients, x, cutoff, term_rows, finite_sum, complete_support_included, certificate]] Conditions: none
List the full source field order without JavaScript,keeping original data,Boolean flags,mathematical objects and nonclaims distinct.
Step identifiers and dependencies Rule: source_ordered_fields_without_JS · Uses: G001
S002 · implies Before
source roles = [[13, 26, 39]] After
derived = [[13, 26, 39], a_n=0 for EVERY n beyond this finite list] Conditions: none
Trim only canonical trailing zeros without changing inputs,retaining at least one coefficient.This defines the entire sequence with its zero tail,not an observed prefix or the EGF coefficient a_n/n!.
Step identifiers and dependencies Rule: OGF_complete_finite_support_zero_tail_NOT_unknown_prefix · Uses: G001, S001
S003 · implies Before
(1/2)^0 After
OGF ORIGINAL x power0 = 1 Conditions: none
Evaluate the finite nonnegative-integer power exactly; exponent0 uses the polynomial multiplicative identity.
Step identifiers and dependencies Rule: integer_power · Uses: G001, S002
S004 · calculation Before
OGF term0 coefficient times power := mul(13, 1) After
OGF term0 coefficient times power = 13 Conditions: none
Substitute original roles and established intermediates exactly,checking nonzero denominators without floats.
Step identifiers and dependencies Rule: exact_rational_arithmetic · Uses: G001, S003
S005 · calculation Before
OGF partial sum through0 := sum(0, 13) After
OGF partial sum through0 = 13 Conditions: none
Substitute original roles and established intermediates exactly,checking nonzero denominators without floats.
Step identifiers and dependencies Rule: exact_rational_arithmetic · Uses: G001, S004
S006 · implies Before
(1/2)^1 After
OGF ORIGINAL x power1 = 1/2 Conditions: none
Evaluate the finite nonnegative-integer power exactly; exponent0 uses the polynomial multiplicative identity.
Step identifiers and dependencies Rule: integer_power · Uses: G001, S005
S007 · calculation Before
OGF term1 coefficient times power := mul(26, 1/2) After
OGF term1 coefficient times power = 13 Conditions: none
Substitute original roles and established intermediates exactly,checking nonzero denominators without floats.
Step identifiers and dependencies Rule: exact_rational_arithmetic · Uses: G001, S006
S008 · calculation Before
OGF partial sum through1 := sum(13, 13) After
OGF partial sum through1 = 26 Conditions: none
Substitute original roles and established intermediates exactly,checking nonzero denominators without floats.
Step identifiers and dependencies Rule: exact_rational_arithmetic · Uses: G001, S007
S009 · implies Before
(1/2)^2 After
OGF ORIGINAL x power2 = 1/4 Conditions: none
Evaluate the finite nonnegative-integer power exactly; exponent0 uses the polynomial multiplicative identity.
Step identifiers and dependencies Rule: integer_power · Uses: G001, S008
S010 · calculation Before
OGF term2 coefficient times power := mul(39, 1/4) After
OGF term2 coefficient times power = 39/4 Conditions: none
Substitute original roles and established intermediates exactly,checking nonzero denominators without floats.
Step identifiers and dependencies Rule: exact_rational_arithmetic · Uses: G001, S009
S011 · calculation Before
OGF partial sum through2 := sum(26, 39/4) After
OGF partial sum through2 = 143/4 Conditions: none
Substitute original roles and established intermediates exactly,checking nonzero denominators without floats.
Step identifiers and dependencies Rule: exact_rational_arithmetic · Uses: G001, S010
S012 · implies Before
source roles = [[13, 26, 39], 1/2, 2] After
derived = [143/4, Yes] Conditions: none
The coverage flag compares cutoff with the final nonzero support,not accidental point equality.At x=0 or by cancellation,a shorter sum may have the same value.
Step identifiers and dependencies Rule: OGF_support_coverage_NOT_accidental_pointwise_equality · Uses: G001, S011
Reverse checks 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 OGF partial sum through2 with exact rational arithmetic, not rounded decimals.S010 · premise_and_result_audit — Recompute OGF term2 coefficient times power with exact rational arithmetic, not rounded decimals.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 OGF partial sum through1 with exact rational arithmetic, not rounded decimals.S007 · premise_and_result_audit — Recompute OGF term1 coefficient times power with exact rational arithmetic, not rounded decimals.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 OGF partial sum through0 with exact rational arithmetic, not rounded decimals.S004 · premise_and_result_audit — Recompute OGF term0 coefficient times power 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 ([13, 26, 39], 1/2, 2, [[0, 13, 13], [1, 26, 13], [2, 39, 39/4]], 143/4, Yes, finite_partial_sum_equals_the_full_OGF_only_after_all_nonzero_finite_support_coefficients_are_included) 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: 0f7be61e2c22317a4075561dc822c87d881a50dboriginal question SHA-256: cee3cc83d267c35f1b940cdb87afb1b3a40e54ef87b0ac48a8d2eff5076fb7b6candidate record SHA-256: 6b24f2b3aac92ec52ee68813b73cfb2e1333243f9796d8b807894dd244de04fcsemantic review receipt SHA-256: 049a9e07e69fead88d93b34f0937b9470a06d71c1a8d097058fc83554529bdd0question-first witness SHA-256: 0c71ebb418f3de347d232d159fc25e93036f4ab9166bcfb5ee5b4be86d5c55b9Lean: NOT_RUN · human review: NOT_PERFORMEDSame-source full JSON