Records the census, the 504-entries-not-504-names correction, and the null result on cracking with the arithmetic that makes it a null result rather than a shrug. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01PMRJjbxLqZtsb5Vb7KunPE