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Graph Theory Research Portal

The Second Neighborhood Conjecture
Interactive Presentation Index

An ordered directory of interactive slide decks covering accounting failures, BFS-Lex coordinate systems, layer size decay, back-arc classifications, and structural proof conclusions for the SSNC.

Interactive Digraph Force Simulation

Why Solving This Matters
Solving the Seymour Second Neighborhood Conjecture isn't just about completing a mathematical proof. It's about understanding the architecture of complex systems—networks of people, data, or even pathogens. By addressing this conjecture, we unlock insights into how influence, information, and interactions propagate far beyond immediate connections.
The Importance of Visualizing the Conjecture
In the third appendix of my work, I reference James Robert Brown's insights on the importance of visual representation in understanding complex mathematical concepts. Motivated by his work, I realized that in order to truly grasp the nuances of the conjecture, I needed to see what I was working with.

To make this possible, I turned to HTML Canvas and D3.js, powerful tools that allowed me to create dynamic visualizations of the problem's structure. By mapping out patterns within the conjecture, I could identify key relationships and test hypotheses more effectively.
Non-Seymour Nodes: From Visualization to Definition
During the process of visualizing the conjecture using D3.js, I began to notice a recurring pattern involving proof by contradiction and a minimum counterexample environment. While not a formal proof initially, it provided crucial clarity that advanced my research into the Iterative Load-balance Corollary.
Impact of the Conjecture on Directed Graphs
The conjecture was originally asked about oriented graphs. A similar conjecture was posed (and solved) for tournaments. General directed graphs fail the conjecture because of bi-directional edges, where complete graphs Kn for n ≥ 3 serve as counterexamples. However, extracting a maximal oriented graph allows us to produce a Seymour vertex, revealing the underlying skeleton of the digraph.

Presentation Modules (In Sequential Order)

9 Interactive Slide Decks
Part 01

The Seymour Diamond

Standard neighborhood accounting failures, distance-two ancestry loss, and double counting in $N^+(v) + N^+(w)$ vs $N^{++}(u)$.

8 Slides Launch →
Part 02

BFS-Lex Coordinate System

Theorem 1 well-ordering, transitive 3-cycles, interior vs. exterior sets, back neighbors, and the Minimum Counterexample (MCE).

6 Slides Launch →
Part 03

MCE Without Back Arcs

Degree partition lemma, inductive layer size decay $|R_k| = \delta - k + 1$, Seymour forcing constraints, and exact interior degree bounds.

7 Slides Launch →
Part 04

Disconnected Back Neighbors

$\delta$-regularity constraints prior to first back arcs, disjoint back neighbor bounds, and well-founded sequence loop closure termination.

5 Slides Launch →
Part 05

Connected Back Neighbors

Analysis of the first connected back arc case, full layer exterior capacity saturation, and the bi-directional arc contradiction proof.

5 Slides Launch →
Part 06

Graph Level Order & Quotients

Quotient hyper-graph equivalence, Hierholzer's cycle algorithm, 8-case load-balancing triangle table, and Seymour diamond resolutions.

6 Slides Launch →
Part 07 (Conclusion)

Proof Synthesis, Collapse Zone & Algorithmic Complexity

Feasibility bounds combining $|R_i| \cdot i \le \binom{|R_i|}{2}$ with layer decay to establish collapse thresholds and optimal complexity.

5 Slides Launch →
Part 08

EvidencePress Counterexample Is NOT an MCE

Reviewing requirements to pack non-Seymour vertices, and noting why the graph provided contains multiple Seymour vertices.

5 Slides Launch →

Graph Theory & Second Neighborhood Conjecture Research Portal • Interactive Presentation Suite