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Question 26056: A Cover Can Resist Every Single Deletion yet Be Larger than Another Cover

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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R0051-26056 · q-20261015-advance-20261115-r06-minimum-vertex-cover-0056

Original question and givens

Use complete unique vertices=[c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6] and loop-free duplicate-free undirected edges=[[c0, l0_0], [c0, l0_1], [c0, l0_2], [c0, l0_3], [c0, l0_4], [c0, l0_5], [c0, l0_6]], candidate cover=[l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6]. An edge needs at least one selected endpoint. Preserve source canonical subset order. Give (candidate, deletion_rows, inclusion_minimal, minimum_size, smaller_cover, minimum, certificate).

  • G001 — Use complete unique vertices=[c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6] and loop-free duplicate-free undirected edges=[[c0, l0_0], [c0, l0_1], [c0, l0_2], [c0, l0_3], [c0, l0_4], [c0, l0_5], [c0, l0_6]], candidate cover=[l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6]. An edge needs at least one selected endpoint. Preserve source canonical subset order. Give (candidate, deletion_rows, inclusion_minimal, minimum_size, smaller_cover, minimum, 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 = [mincover-minimal-not-minimum]

After

derived = [[candidate, deletion_rows, inclusion_minimal, minimum_size, smaller_cover, minimum, certificate]]

Conditions: none

List the full source field order without JavaScript.Original modes select contract6/4/6/6 and IVT8/7/8 roles,without padding or answer-shape inference.

Step identifiers and dependencies

Rule: source_ordered_fields_without_JS · Uses: G001

S002 · implies

Before

source roles = [[c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [[c0, l0_0], [c0, l0_1], [c0, l0_2], [c0, l0_3], [c0, l0_4], [c0, l0_5], [c0, l0_6]], [l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6]]

After

derived = [[c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [[c0, l0_0], [c0, l0_1], [c0, l0_2], [c0, l0_3], [c0, l0_4], [c0, l0_5], [c0, l0_6]], [l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6]]

Conditions: none

The carrier is nonempty with at most12 vertices;sort endpoints by UTF16 then edge families in English.Reject loops/reversed duplicates.An omitted candidate stays null,not an invented empty candidate.

Step identifiers and dependencies

Rule: Mincover_complete_simple_graph_UTF16_English_and_optional_candidate · Uses: G001, S001

S003 · implies

Before

source roles = [[c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [[c0, l0_0], [c0, l0_1], [c0, l0_2], [c0, l0_3], [c0, l0_4], [c0, l0_5], [c0, l0_6]], 256]

After

derived = [[1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, 181, 183, 185, 187, 189, 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 254, 255], [[0, 0], [2, 1], [4, 0], [6, 2], [8, 0], [10, 1], [12, 0], [14, 3], [16, 0], [18, 1], [20, 0], [22, 2], [24, 0], [26, 1], [28, 0], [30, 4], [32, 0], [34, 1], [36, 0], [38, 2], [40, 0], [42, 1], [44, 0], [46, 3], [48, 0], [50, 1], [52, 0], [54, 2], [56, 0], [58, 1], [60, 0], [62, 5], [64, 0], [66, 1], [68, 0], [70, 2], [72, 0], [74, 1], [76, 0], [78, 3], [80, 0], [82, 1], [84, 0], [86, 2], [88, 0], [90, 1], [92, 0], [94, 4], [96, 0], [98, 1], [100, 0], [102, 2], [104, 0], [106, 1], [108, 0], [110, 3], [112, 0], [114, 1], [116, 0], [118, 2], [120, 0], [122, 1], [124, 0], [126, 6], [128, 0], [130, 1], [132, 0], [134, 2], [136, 0], [138, 1], [140, 0], [142, 3], [144, 0], [146, 1], [148, 0], [150, 2], [152, 0], [154, 1], [156, 0], [158, 4], [160, 0], [162, 1], [164, 0], [166, 2], [168, 0], [170, 1], [172, 0], [174, 3], [176, 0], [178, 1], [180, 0], [182, 2], [184, 0], [186, 1], [188, 0], [190, 5], [192, 0], [194, 1], [196, 0], [198, 2], [200, 0], [202, 1], [204, 0], [206, 3], [208, 0], [210, 1], [212, 0], [214, 2], [216, 0], [218, 1], [220, 0], [222, 4], [224, 0], [226, 1], [228, 0], [230, 2], [232, 0], [234, 1], [236, 0], [238, 3], [240, 0], [242, 1], [244, 0], [246, 2], [248, 0], [250, 1], [252, 0]], [[c0], [c0, l0_0], [c0, l0_1], [c0, l0_0, l0_1], [c0, l0_2], [c0, l0_0, l0_2], [c0, l0_1, l0_2], [c0, l0_0, l0_1, l0_2], [c0, l0_3], [c0, l0_0, l0_3], [c0, l0_1, l0_3], [c0, l0_0, l0_1, l0_3], [c0, l0_2, l0_3], [c0, l0_0, l0_2, l0_3], [c0, l0_1, l0_2, l0_3], [c0, l0_0, l0_1, l0_2, l0_3], [c0, l0_4], [c0, l0_0, l0_4], [c0, l0_1, l0_4], [c0, l0_0, l0_1, l0_4], [c0, l0_2, l0_4], [c0, l0_0, l0_2, l0_4], [c0, l0_1, l0_2, l0_4], [c0, l0_0, l0_1, l0_2, l0_4], [c0, l0_3, l0_4], [c0, l0_0, l0_3, l0_4], [c0, l0_1, l0_3, l0_4], [c0, l0_0, l0_1, l0_3, l0_4], [c0, l0_2, l0_3, l0_4], [c0, l0_0, l0_2, l0_3, l0_4], [c0, l0_1, l0_2, l0_3, l0_4], [c0, l0_0, l0_1, l0_2, l0_3, l0_4], [c0, l0_5], [c0, l0_0, l0_5], [c0, l0_1, l0_5], [c0, l0_0, l0_1, l0_5], [c0, l0_2, l0_5], [c0, l0_0, l0_2, l0_5], [c0, l0_1, l0_2, l0_5], [c0, l0_0, l0_1, l0_2, l0_5], [c0, l0_3, l0_5], [c0, l0_0, l0_3, l0_5], [c0, l0_1, l0_3, l0_5], [c0, l0_0, l0_1, l0_3, l0_5], [c0, l0_2, l0_3, l0_5], [c0, l0_0, l0_2, l0_3, l0_5], [c0, l0_1, l0_2, l0_3, l0_5], [c0, l0_0, l0_1, l0_2, l0_3, l0_5], [c0, l0_4, l0_5], [c0, l0_0, l0_4, l0_5], [c0, l0_1, l0_4, l0_5], [c0, l0_0, l0_1, l0_4, l0_5], [c0, l0_2, l0_4, l0_5], [c0, l0_0, l0_2, l0_4, l0_5], [c0, l0_1, l0_2, l0_4, l0_5], [c0, l0_0, l0_1, l0_2, l0_4, l0_5], [c0, l0_3, l0_4, l0_5], [c0, l0_0, l0_3, l0_4, l0_5], [c0, l0_1, l0_3, l0_4, l0_5], [c0, l0_0, l0_1, l0_3, l0_4, l0_5], [c0, l0_2, l0_3, l0_4, l0_5], [c0, l0_0, l0_2, l0_3, l0_4, l0_5], [c0, l0_1, l0_2, l0_3, l0_4, l0_5], [c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5], [c0, l0_6], [c0, l0_0, l0_6], [c0, l0_1, l0_6], [c0, l0_0, l0_1, l0_6], [c0, l0_2, l0_6], [c0, l0_0, l0_2, l0_6], [c0, l0_1, l0_2, l0_6], [c0, l0_0, l0_1, l0_2, l0_6], [c0, l0_3, l0_6], [c0, l0_0, l0_3, l0_6], [c0, l0_1, l0_3, l0_6], [c0, l0_0, l0_1, l0_3, l0_6], [c0, l0_2, l0_3, l0_6], [c0, l0_0, l0_2, l0_3, l0_6], [c0, l0_1, l0_2, l0_3, l0_6], [c0, l0_0, l0_1, l0_2, l0_3, l0_6], [c0, l0_4, l0_6], [c0, l0_0, l0_4, l0_6], [c0, l0_1, l0_4, l0_6], [c0, l0_0, l0_1, l0_4, l0_6], [c0, l0_2, l0_4, l0_6], [c0, l0_0, l0_2, l0_4, l0_6], [c0, l0_1, l0_2, l0_4, l0_6], [c0, l0_0, l0_1, l0_2, l0_4, l0_6], [c0, l0_3, l0_4, l0_6], [c0, l0_0, l0_3, l0_4, l0_6], [c0, l0_1, l0_3, l0_4, l0_6], [c0, l0_0, l0_1, l0_3, l0_4, l0_6], [c0, l0_2, l0_3, l0_4, l0_6], [c0, l0_0, l0_2, l0_3, l0_4, l0_6], [c0, l0_1, l0_2, l0_3, l0_4, l0_6], [c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_6], [c0, l0_5, l0_6], [c0, l0_0, l0_5, l0_6], [c0, l0_1, l0_5, l0_6], [c0, l0_0, l0_1, l0_5, l0_6], [c0, l0_2, l0_5, l0_6], [c0, l0_0, l0_2, l0_5, l0_6], [c0, l0_1, l0_2, l0_5, l0_6], [c0, l0_0, l0_1, l0_2, l0_5, l0_6], [c0, l0_3, l0_5, l0_6], [c0, l0_0, l0_3, l0_5, l0_6], [c0, l0_1, l0_3, l0_5, l0_6], [c0, l0_0, l0_1, l0_3, l0_5, l0_6], [c0, l0_2, l0_3, l0_5, l0_6], [c0, l0_0, l0_2, l0_3, l0_5, l0_6], [c0, l0_1, l0_2, l0_3, l0_5, l0_6], [c0, l0_0, l0_1, l0_2, l0_3, l0_5, l0_6], [c0, l0_4, l0_5, l0_6], [c0, l0_0, l0_4, l0_5, l0_6], [c0, l0_1, l0_4, l0_5, l0_6], [c0, l0_0, l0_1, l0_4, l0_5, l0_6], [c0, l0_2, l0_4, l0_5, l0_6], [c0, l0_0, l0_2, l0_4, l0_5, l0_6], [c0, l0_1, l0_2, l0_4, l0_5, l0_6], [c0, l0_0, l0_1, l0_2, l0_4, l0_5, l0_6], [c0, l0_3, l0_4, l0_5, l0_6], [c0, l0_0, l0_3, l0_4, l0_5, l0_6], [c0, l0_1, l0_3, l0_4, l0_5, l0_6], [c0, l0_0, l0_1, l0_3, l0_4, l0_5, l0_6], [c0, l0_2, l0_3, l0_4, l0_5, l0_6], [c0, l0_0, l0_2, l0_3, l0_4, l0_5, l0_6], [c0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [c0, l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6]], [0, 1, 7, 21, 35, 35, 21, 8, 1], 1, [[c0]]]

Conditions: none

Audit every mask against every edge,retaining the first uncovered-edge refutation for each failure and every accepted set in source order.Zero smaller-size counts give a lower bound and actual minimum covers attain it.Keep all ties in numeric-mask order,not English/size order.

Step identifiers and dependencies

Rule: Mincover_ALL_masks_acceptance_refutations_ALLcovers_ALLminimizers · Uses: G001, S002

S004 · implies

Before

source roles = [[l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [[c0, l0_0], [c0, l0_1], [c0, l0_2], [c0, l0_3], [c0, l0_4], [c0, l0_5], [c0, l0_6]]]

After

derived = [[[[c0, l0_0], Yes], [[c0, l0_1], Yes], [[c0, l0_2], Yes], [[c0, l0_3], Yes], [[c0, l0_4], Yes], [[c0, l0_5], Yes], [[c0, l0_6], Yes]], 7, 1, [c0]]

Conditions: none

First qualify an actual candidate cover.The smaller witness is the first minimum from the complete source list,not an arbitrary small set.

Step identifiers and dependencies

Rule: Mincover_actual_candidate_complete_cover_and_smaller_witness · Uses: G001, S003

S005 · implies

Before

source roles = [[l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [[l0_0, [l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], No], [l0_1, [l0_0, l0_2, l0_3, l0_4, l0_5, l0_6], No], [l0_2, [l0_0, l0_1, l0_3, l0_4, l0_5, l0_6], No], [l0_3, [l0_0, l0_1, l0_2, l0_4, l0_5, l0_6], No], [l0_4, [l0_0, l0_1, l0_2, l0_3, l0_5, l0_6], No], [l0_5, [l0_0, l0_1, l0_2, l0_3, l0_4, l0_6], No], [l0_6, [l0_0, l0_1, l0_2, l0_3, l0_4, l0_5], No]]]

After

derived = [Yes, 1, [c0], No]

Conditions: none

Every single deletion loses coverage,so the candidate is inclusion-minimal.But exhaustive search supplies a strictly smaller cover,so it is not minimum.Superset monotonicity makes deletion tests cover all proper-subset obligations,not maximum or optimal size.

Step identifiers and dependencies

Rule: Mincover_ALL_single_deletions_minimal_BUT_smaller_cover_exists · Uses: G001, S004

Reverse checks

  • S005 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • 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 — 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

([l0_0, l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], [[l0_0, [l0_1, l0_2, l0_3, l0_4, l0_5, l0_6], No], [l0_1, [l0_0, l0_2, l0_3, l0_4, l0_5, l0_6], No], [l0_2, [l0_0, l0_1, l0_3, l0_4, l0_5, l0_6], No], [l0_3, [l0_0, l0_1, l0_2, l0_4, l0_5, l0_6], No], [l0_4, [l0_0, l0_1, l0_2, l0_3, l0_5, l0_6], No], [l0_5, [l0_0, l0_1, l0_2, l0_3, l0_4, l0_6], No], [l0_6, [l0_0, l0_1, l0_2, l0_3, l0_4, l0_5], No]], Yes, 1, [c0], No, inclusion_minimal_is_not_minimum)

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: fe3d8634b107f37b5bb532168681444d1d3ef1e439b37f09fab1cb89e6f50160
  • candidate record SHA-256: c56f24e82ee6a226a40869e01eec3bc641a23114700de3a905521c880e809421
  • semantic review receipt SHA-256: 90df1e889242e9afdf01e068788ee8500ef366ffcfc0496e30a6800de32631c3
  • question-first witness SHA-256: ae1e849608590ca856c9f3b6911ba58e3bf53c608eb7369606192a770f48bd5c
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON