{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2020:B6XLRHZ6GGPX4XQMSVXOV46H2O","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"2a4c8b42115cae0fce2d48e82dd74b4eeff3af3366bbffaa68d59e6a1b124d7d","cross_cats_sorted":["cs.CG"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CC","submitted_at":"2020-03-18T16:54:28Z","title_canon_sha256":"d361a1dd54229f626913c882a0a5c31dbe9165ae4767b2135ad5914c32274222"},"schema_version":"1.0","source":{"id":"2003.08331","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2003.08331","created_at":"2026-07-05T01:01:24Z"},{"alias_kind":"arxiv_version","alias_value":"2003.08331v2","created_at":"2026-07-05T01:01:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2003.08331","created_at":"2026-07-05T01:01:24Z"},{"alias_kind":"pith_short_12","alias_value":"B6XLRHZ6GGPX","created_at":"2026-07-05T01:01:24Z"},{"alias_kind":"pith_short_16","alias_value":"B6XLRHZ6GGPX4XQM","created_at":"2026-07-05T01:01:24Z"},{"alias_kind":"pith_short_8","alias_value":"B6XLRHZ6","created_at":"2026-07-05T01:01:24Z"}],"graph_snapshots":[{"event_id":"sha256:015ad606e36d8df6dd17ef53ddc844326632a38f57ec1fb012a953166e012fc6","target":"graph","created_at":"2026-07-05T01:01:24Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2003.08331/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In the Nikoli pencil-and-paper game Tatamibari, a puzzle consists of an $m \\times n$ grid of cells, where each cell possibly contains a clue among +, -, |. The goal is to partition the grid into disjoint rectangles, where every rectangle contains exactly one clue, rectangles containing + are square, rectangles containing - are strictly longer horizontally than vertically, rectangles containing | are strictly longer vertically than horizontally, and no four rectangles share a corner. We prove this puzzle NP-complete, establishing a Nikoli gap of 16 years. Along the way, we introduce a gadget fr","authors_text":"Aviv Adler, Erik D. Demaine, Jayson Lynch, Jeffrey Bosboom, Martin L. Demaine, Quanquan C. Liu","cross_cats":["cs.CG"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CC","submitted_at":"2020-03-18T16:54:28Z","title":"Tatamibari is NP-complete"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2003.08331","kind":"arxiv","version":2},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:9aff3060279a39fea26589c6433e56e4299a8931cbe6398fb326b3def81382e9","target":"record","created_at":"2026-07-05T01:01:24Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"2a4c8b42115cae0fce2d48e82dd74b4eeff3af3366bbffaa68d59e6a1b124d7d","cross_cats_sorted":["cs.CG"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CC","submitted_at":"2020-03-18T16:54:28Z","title_canon_sha256":"d361a1dd54229f626913c882a0a5c31dbe9165ae4767b2135ad5914c32274222"},"schema_version":"1.0","source":{"id":"2003.08331","kind":"arxiv","version":2}},"canonical_sha256":"0faeb89f3e319f7e5e0c956eeaf3c7d3ba892e6b0b0e3a332cd3a1c7e6148bb1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0faeb89f3e319f7e5e0c956eeaf3c7d3ba892e6b0b0e3a332cd3a1c7e6148bb1","first_computed_at":"2026-07-05T01:01:24.013403Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T01:01:24.013403Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"3MvVUS6dmXAZ4cQ5ZY8i1INfGIrKAqKHORbSex638424j6otZXOXDAbzuuVFcO2rES3AphhxsoyU85Gd+PQIBA==","signature_status":"signed_v1","signed_at":"2026-07-05T01:01:24.013897Z","signed_message":"canonical_sha256_bytes"},"source_id":"2003.08331","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:9aff3060279a39fea26589c6433e56e4299a8931cbe6398fb326b3def81382e9","sha256:015ad606e36d8df6dd17ef53ddc844326632a38f57ec1fb012a953166e012fc6"],"state_sha256":"2dda3f0cc8c199575c07b85d1c52b945c35278c2ce5d55fb162496e621bdde17"}