Explore related knowledge and questions →

Question 15582: Audit This Bipartition without Misclassifying the Entire Graph

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 78

← Question derivation index · Original question batch

R0030-15582 · q-20261014-advance-20261031-r02-bipartite-graph-0007

Original question and givens

Use the complete finite undirected loop-free simple graph on Fin(6)={0,…,5} with edges=[[0, 1], [1, 2], [2, 3], [3, 4]]. Normalize each edge increasingly, then sort edges lexicographically; reversed duplicates and loops are forbidden. Keep isolated vertices in the carrier. No directed-graph conclusion is inferred. The total part assignment=[0, 1, 1, 0, 0, 0] uses labels 0 or 1 for every vertex. Its two inverse-image parts are disjoint and cover the whole carrier. Every edge must cross parts; empty parts are allowed in an edgeless graph. Failure of this assignment alone does not prove the graph nonbipartite. Give (parts,conflicting_edges,proper?,classification). List all same-part edges in normalized edge order. Classification is bipartition_certificate or this_partition_fails_not_nonbipartite_proof.

  • G001 — Use the complete finite undirected loop-free simple graph on Fin(6)={0,…,5} with edges=[[0, 1], [1, 2], [2, 3], [3, 4]]. Normalize each edge increasingly, then sort edges lexicographically; reversed duplicates and loops are forbidden. Keep isolated vertices in the carrier. No directed-graph conclusion is inferred. The total part assignment=[0, 1, 1, 0, 0, 0] uses labels 0 or 1 for every vertex. Its two inverse-image parts are disjoint and cover the whole carrier. Every edge must cross parts; empty parts are allowed in an edgeless graph. Failure of this assignment alone does not prove the graph nonbipartite. Give (parts,conflicting_edges,proper?,classification). List all same-part edges in normalized edge order. Classification is bipartition_certificate or this_partition_fails_not_nonbipartite_proof.

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

complete undirected vertex carrier Fin(6);original edges=[[0, 1], [1, 2], [2, 3], [3, 4]]

After

normalized sorted simple edges=[[0, 1], [1, 2], [2, 3], [3, 4]];all vertices including isolates=[0, 1, 2, 3, 4, 5]

Conditions: none

Normalize endpoints and then sort edges lexicographically.Reversed duplicates are still duplicates and are rejected,as are loops.The complete carrier includes vertices absent from the edge list.

Step identifiers and dependencies

Rule: graph_complete_simple_carrier_normalized_edge_order · Uses: G001

S002 · implies

Before

total original part labels=[0, 1, 1, 0, 0, 0];complete carrier Fin(6)

After

part0=[0, 3, 4, 5];part1=[1, 2];disjoint full cover=Yes

Conditions: none

The two inverse images of0 and1 are disjoint and cover every originally labeled vertex.An empty part is allowed for an edgeless graph;isolates remain included.Edge crossing is still a separate obligation.

Step identifiers and dependencies

Rule: bipartition_total_inverse_image_parts · Uses: G001, S001

S003 · implies

Before

parts:normalized edge index=0;edge=[0, 1];endpoint labels=[0, 1]

After

different endpoints=Yes;same-label conflict=No

Conditions: none

Check the endpoints of each actual edge.Reused labels at nonadjacent vertices are not conflicts,and one crossing edge does not certify all other edges.

Step identifiers and dependencies

Rule: graph_every_edge_endpoint_constraint · Uses: G001, S002

S004 · implies

Before

parts:normalized edge index=1;edge=[1, 2];endpoint labels=[1, 1]

After

different endpoints=No;same-label conflict=Yes

Conditions: none

Check the endpoints of each actual edge.Reused labels at nonadjacent vertices are not conflicts,and one crossing edge does not certify all other edges.

Step identifiers and dependencies

Rule: graph_every_edge_endpoint_constraint · Uses: G001, S003

S005 · implies

Before

parts:normalized edge index=2;edge=[2, 3];endpoint labels=[1, 0]

After

different endpoints=Yes;same-label conflict=No

Conditions: none

Check the endpoints of each actual edge.Reused labels at nonadjacent vertices are not conflicts,and one crossing edge does not certify all other edges.

Step identifiers and dependencies

Rule: graph_every_edge_endpoint_constraint · Uses: G001, S004

S006 · implies

Before

parts:normalized edge index=3;edge=[3, 4];endpoint labels=[0, 0]

After

different endpoints=No;same-label conflict=Yes

Conditions: none

Check the endpoints of each actual edge.Reused labels at nonadjacent vertices are not conflicts,and one crossing edge does not certify all other edges.

Step identifiers and dependencies

Rule: graph_every_edge_endpoint_constraint · Uses: G001, S005

S007 · implies

Before

all normalized same-part edges=[[1, 2], [3, 4]];total part assignment=[0, 1, 1, 0, 0, 0]

After

whole assignment proper=No;classification=this_partition_fails_not_nonbipartite_proof

Conditions: none

No conflicts certify this assignment.Conflicts refute only these part labels,not every possible bipartition;graph nonbipartiteness needs a separate obstruction such as an actual odd cycle.

Step identifiers and dependencies

Rule: bipartite_whole_assignment_not_graph_impossibility · Uses: G001, S006

Reverse checks

  • 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 — 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

([0, 1, 1, 0, 0, 0], [[1, 2], [3, 4]], No, this_partition_fails_not_nonbipartite_proof)

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: 55bbe17de4211898281383c9f9dfe9df25268814c7321f13b4790fc7ec861707
  • candidate record SHA-256: 02cd7af0a722e2978c01fd48e4bd3afd9a0702c7d89f335b493eef771d2a2b57
  • semantic review receipt SHA-256: 73bc08066ffb1a81eacb2d4e288d03f522aeefd3949fa0d97da41b484ed737bc
  • question-first witness SHA-256: ac120452a208b257b8270f38351a09dcd832cdbc8d9db6b69933f83e43cc9336
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON