[Superseded] Formalize OEIS A147983 Chomp three-opening challenge

[DomTheDeveloper]

Superseded by #185.

The corrected computational artifact is stored only on the dedicated DomTheDeveloper/formal-conjectures branch proof-artifacts/oeis-a147983-chomp:

https://github.com/DomTheDeveloper/formal-conjectures/tree/a0c8858ce9b22166d0616931ea1fc996e335b03d/ProofArtifacts/OEIS/A147983

[github-actions]

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