Commit Graph

2 Commits

Author SHA1 Message Date
didericis ad3f95fa39 Move root experiment scripts into their papers' experiments/ folders
Relocate the standalone Python scripts from the repo root into the
experiments/ folder of the paper each one belongs to:

  plane_depth_sequencing/experiments/
    plane_depth_sequencing.py, draw_quad_sequence.py,
    draw_quad_sequence_diagram.py, extract_sequence.py,
    plane_depth_sequencing_figure.py, quad_sequence_coloring_check.py
  colored_edge_flip_classes/experiments/   colored_edge_flip_class_survey.py
  colored_pentagon_contractions/experiments/ colored_pentagon_contractions.py
  plane_diamond_coloring/experiments/       plane_diamond_coloring.py

Each file that imports lib.* (still in the repo root) or the sibling
plane_depth_sequencing module gets a sys.path shim that prepends the
repo root (computed three levels up) and, where needed, its own dir.
Imports verified to resolve from a neutral working directory.

flip_symmetric_census.py is intentionally left in the root.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-22 10:40:39 -04:00
didericis 1a71658349 Small-n bridge-derivability probe: classification + invariant search
Findings at n=9 (50 triangulations, orbits fully exhaustible):
- 36 bridge-derived, 14 NOT bridge-derived. So bridge-derived is a PROPER
  subclass of derived (49 derived at n=9). All 14 non-bridge graphs are
  intertwining trees -- as are all 50, necessarily: intertwining tree
  <=> dual Hamiltonian, and the smallest non-Hamiltonian 3-connected cubic
  planar graph has 38 vertices, i.e. dual on 2n-4=38 => n=21. Hence every
  triangulation with n<=20 is an intertwining tree, and the disjunction
  "bridge-derived OR intertwining" is trivially true below n=21. The 4
  Holton-McKay duals are the first non-intertwining triangulations.
- Static parity-subgraph invariants (Betti numbers, component counts,
  cross-edge count, existence of an all-forest partition) do NOT separate
  bridge-derived from non-bridge-derived -- both classes realize beta=0
  partitions and identical ranges. Bridge-derivability is dynamical, not a
  simple static invariant; no easy obstruction.
- Side lemma: every valid parity partition of an n-vertex triangulation has
  exactly 2n-4 cross edges (intra-edges = n-2). Holds for all n=9 graphs.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-22 10:03:04 -04:00