{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:E2KP764UJNR37VC4ZGJG4OMILV","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":"28b43e671628f1d075aa7e8cf2ab164a6a2793b77ccd16b5170a80fc781a771f","cross_cats_sorted":["math.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CC","submitted_at":"2019-08-16T13:31:59Z","title_canon_sha256":"caabe2a933df8faada178d4eaf14c8ea18f53497fc3196f7b4c6b5de0ad565d4"},"schema_version":"1.0","source":{"id":"1908.05966","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1908.05966","created_at":"2026-07-05T00:55:58Z"},{"alias_kind":"arxiv_version","alias_value":"1908.05966v1","created_at":"2026-07-05T00:55:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1908.05966","created_at":"2026-07-05T00:55:58Z"},{"alias_kind":"pith_short_12","alias_value":"E2KP764UJNR3","created_at":"2026-07-05T00:55:58Z"},{"alias_kind":"pith_short_16","alias_value":"E2KP764UJNR37VC4","created_at":"2026-07-05T00:55:58Z"},{"alias_kind":"pith_short_8","alias_value":"E2KP764U","created_at":"2026-07-05T00:55:58Z"}],"graph_snapshots":[{"event_id":"sha256:693de2ad187348d6213ac4072cb64475b20d5357678f634e3795ab96fa0e5d40","target":"graph","created_at":"2026-07-05T00:55:58Z","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/1908.05966/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We show that the classical game LaserTank is $\\mathrm{NP}$-complete, even when the tank movement is restricted to a single column and the only blocks appearing on the board are mirrors and solid blocks. We show this by reducing $3$-SAT instances to LaserTank puzzles.","authors_text":"Per Alexandersson, Petter Restadh","cross_cats":["math.CO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CC","submitted_at":"2019-08-16T13:31:59Z","title":"LaserTank is NP-complete"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1908.05966","kind":"arxiv","version":1},"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:c8242ed7de0f80ba4d301ccc35292b96ad153c0f57f3215636f8aa1b138a0f64","target":"record","created_at":"2026-07-05T00:55:58Z","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":"28b43e671628f1d075aa7e8cf2ab164a6a2793b77ccd16b5170a80fc781a771f","cross_cats_sorted":["math.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CC","submitted_at":"2019-08-16T13:31:59Z","title_canon_sha256":"caabe2a933df8faada178d4eaf14c8ea18f53497fc3196f7b4c6b5de0ad565d4"},"schema_version":"1.0","source":{"id":"1908.05966","kind":"arxiv","version":1}},"canonical_sha256":"2694fffb944b63bfd45cc9926e39885d433dda27ed4897d812fdf0ba19bf2cbe","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2694fffb944b63bfd45cc9926e39885d433dda27ed4897d812fdf0ba19bf2cbe","first_computed_at":"2026-07-05T00:55:58.474576Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T00:55:58.474576Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"Ghr1+vox/1kPbWltyjCMpSeO2U2Z2LMuOXeIpyH6/kp4xdeWPzmkO4LednCQBoRVU1QZJOlJlR3MhCo4v/mWAQ==","signature_status":"signed_v1","signed_at":"2026-07-05T00:55:58.475067Z","signed_message":"canonical_sha256_bytes"},"source_id":"1908.05966","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:c8242ed7de0f80ba4d301ccc35292b96ad153c0f57f3215636f8aa1b138a0f64","sha256:693de2ad187348d6213ac4072cb64475b20d5357678f634e3795ab96fa0e5d40"],"state_sha256":"b6085470e5ffe4f8eaef4e69d460644862f1775fed24701a9ac392a5cf29e829"}