{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:BVSLI25VNCYQLV4YS2IF2FCTC5","short_pith_number":"pith:BVSLI25V","canonical_record":{"source":{"id":"1309.7891","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by-nc-sa/3.0/","primary_cat":"cs.DS","submitted_at":"2013-09-30T15:46:14Z","cross_cats_sorted":["cs.DM"],"title_canon_sha256":"e618026bbead99f516f8423932262850c6a374ab58715ee7ba7770ead65752a8","abstract_canon_sha256":"90ffaae97c85a225011cf5797933930a6260b926c4ffcdc9fbb520fece0477ef"},"schema_version":"1.0"},"canonical_sha256":"0d64b46bb568b105d79896905d14531741b6e47d3385029c7060ff668b09b80d","source":{"kind":"arxiv","id":"1309.7891","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1309.7891","created_at":"2026-05-18T03:11:47Z"},{"alias_kind":"arxiv_version","alias_value":"1309.7891v1","created_at":"2026-05-18T03:11:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1309.7891","created_at":"2026-05-18T03:11:47Z"},{"alias_kind":"pith_short_12","alias_value":"BVSLI25VNCYQ","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_16","alias_value":"BVSLI25VNCYQLV4Y","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_8","alias_value":"BVSLI25V","created_at":"2026-05-18T12:27:40Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:BVSLI25VNCYQLV4YS2IF2FCTC5","target":"record","payload":{"canonical_record":{"source":{"id":"1309.7891","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by-nc-sa/3.0/","primary_cat":"cs.DS","submitted_at":"2013-09-30T15:46:14Z","cross_cats_sorted":["cs.DM"],"title_canon_sha256":"e618026bbead99f516f8423932262850c6a374ab58715ee7ba7770ead65752a8","abstract_canon_sha256":"90ffaae97c85a225011cf5797933930a6260b926c4ffcdc9fbb520fece0477ef"},"schema_version":"1.0"},"canonical_sha256":"0d64b46bb568b105d79896905d14531741b6e47d3385029c7060ff668b09b80d","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:11:47.898655Z","signature_b64":"iC4+eWXfWJ6cL5Tltw1atfqHCo8FGHfaXWD0qvd6jjlpV0Hai9g5e/Nv/Fjb1PMtvRKnK3NtapBJ5+vH/aBlCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"0d64b46bb568b105d79896905d14531741b6e47d3385029c7060ff668b09b80d","last_reissued_at":"2026-05-18T03:11:47.897915Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:11:47.897915Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1309.7891","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T03:11:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KgzHAZSZLvH3aYF7JIbccsmv3ZAftQ5mGtlZ6N+qWuUhVdo0iwZPrhF+aAp2LhT3BIBumO6yaVZ5kUAHbW2YCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-19T16:23:34.180106Z"},"content_sha256":"922f9c143a88da50c9a4cf421ddffa472adcfbcea862881ef6c9e90670a17135","schema_version":"1.0","event_id":"sha256:922f9c143a88da50c9a4cf421ddffa472adcfbcea862881ef6c9e90670a17135"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:BVSLI25VNCYQLV4YS2IF2FCTC5","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Tree Deletion Set has a Polynomial Kernel (but no OPT^O(1) approximation)","license":"http://creativecommons.org/licenses/by-nc-sa/3.0/","headline":"","cross_cats":["cs.DM"],"primary_cat":"cs.DS","authors_text":"Archontia C. Giannopoulou, Daniel Lokshtanov, Ondrej Suchy, Saket Saurabh","submitted_at":"2013-09-30T15:46:14Z","abstract_excerpt":"In the Tree Deletion Set problem the input is a graph G together with an integer k. The objective is to determine whether there exists a set S of at most k vertices such that G-S is a tree. The problem is NP-complete and even NP-hard to approximate within any factor of OPT^c for any constant c. In this paper we give a O(k^4) size kernel for the Tree Deletion Set problem. To the best of our knowledge our result is the first counterexample to the \"conventional wisdom\" that kernelization algorithms automatically provide approximation algorithms with approximation ratio close to the size of the ke"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1309.7891","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T03:11:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"UBKop4K3p+qBsxx3eyRpm0AyAjPa/l/3oqxp1LuRHKXhu2Q7CwMO1/m92cRw0jgKcvIomwzDAs78Xk5SMXWdCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-19T16:23:34.180472Z"},"content_sha256":"0bc96a456455b4a55c458ed2959f78d9cf596c84c0504cc101772594da55726d","schema_version":"1.0","event_id":"sha256:0bc96a456455b4a55c458ed2959f78d9cf596c84c0504cc101772594da55726d"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/BVSLI25VNCYQLV4YS2IF2FCTC5/bundle.json","state_url":"https://pith.science/pith/BVSLI25VNCYQLV4YS2IF2FCTC5/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/BVSLI25VNCYQLV4YS2IF2FCTC5/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-19T16:23:34Z","links":{"resolver":"https://pith.science/pith/BVSLI25VNCYQLV4YS2IF2FCTC5","bundle":"https://pith.science/pith/BVSLI25VNCYQLV4YS2IF2FCTC5/bundle.json","state":"https://pith.science/pith/BVSLI25VNCYQLV4YS2IF2FCTC5/state.json","well_known_bundle":"https://pith.science/.well-known/pith/BVSLI25VNCYQLV4YS2IF2FCTC5/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:BVSLI25VNCYQLV4YS2IF2FCTC5","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":"90ffaae97c85a225011cf5797933930a6260b926c4ffcdc9fbb520fece0477ef","cross_cats_sorted":["cs.DM"],"license":"http://creativecommons.org/licenses/by-nc-sa/3.0/","primary_cat":"cs.DS","submitted_at":"2013-09-30T15:46:14Z","title_canon_sha256":"e618026bbead99f516f8423932262850c6a374ab58715ee7ba7770ead65752a8"},"schema_version":"1.0","source":{"id":"1309.7891","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1309.7891","created_at":"2026-05-18T03:11:47Z"},{"alias_kind":"arxiv_version","alias_value":"1309.7891v1","created_at":"2026-05-18T03:11:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1309.7891","created_at":"2026-05-18T03:11:47Z"},{"alias_kind":"pith_short_12","alias_value":"BVSLI25VNCYQ","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_16","alias_value":"BVSLI25VNCYQLV4Y","created_at":"2026-05-18T12:27:40Z"},{"alias_kind":"pith_short_8","alias_value":"BVSLI25V","created_at":"2026-05-18T12:27:40Z"}],"graph_snapshots":[{"event_id":"sha256:0bc96a456455b4a55c458ed2959f78d9cf596c84c0504cc101772594da55726d","target":"graph","created_at":"2026-05-18T03:11:47Z","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"},"paper":{"abstract_excerpt":"In the Tree Deletion Set problem the input is a graph G together with an integer k. The objective is to determine whether there exists a set S of at most k vertices such that G-S is a tree. The problem is NP-complete and even NP-hard to approximate within any factor of OPT^c for any constant c. In this paper we give a O(k^4) size kernel for the Tree Deletion Set problem. To the best of our knowledge our result is the first counterexample to the \"conventional wisdom\" that kernelization algorithms automatically provide approximation algorithms with approximation ratio close to the size of the ke","authors_text":"Archontia C. Giannopoulou, Daniel Lokshtanov, Ondrej Suchy, Saket Saurabh","cross_cats":["cs.DM"],"headline":"","license":"http://creativecommons.org/licenses/by-nc-sa/3.0/","primary_cat":"cs.DS","submitted_at":"2013-09-30T15:46:14Z","title":"Tree Deletion Set has a Polynomial Kernel (but no OPT^O(1) approximation)"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1309.7891","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":"sha256:922f9c143a88da50c9a4cf421ddffa472adcfbcea862881ef6c9e90670a17135","target":"record","created_at":"2026-05-18T03:11:47Z","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":"90ffaae97c85a225011cf5797933930a6260b926c4ffcdc9fbb520fece0477ef","cross_cats_sorted":["cs.DM"],"license":"http://creativecommons.org/licenses/by-nc-sa/3.0/","primary_cat":"cs.DS","submitted_at":"2013-09-30T15:46:14Z","title_canon_sha256":"e618026bbead99f516f8423932262850c6a374ab58715ee7ba7770ead65752a8"},"schema_version":"1.0","source":{"id":"1309.7891","kind":"arxiv","version":1}},"canonical_sha256":"0d64b46bb568b105d79896905d14531741b6e47d3385029c7060ff668b09b80d","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0d64b46bb568b105d79896905d14531741b6e47d3385029c7060ff668b09b80d","first_computed_at":"2026-05-18T03:11:47.897915Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:11:47.897915Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"iC4+eWXfWJ6cL5Tltw1atfqHCo8FGHfaXWD0qvd6jjlpV0Hai9g5e/Nv/Fjb1PMtvRKnK3NtapBJ5+vH/aBlCA==","signature_status":"signed_v1","signed_at":"2026-05-18T03:11:47.898655Z","signed_message":"canonical_sha256_bytes"},"source_id":"1309.7891","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:922f9c143a88da50c9a4cf421ddffa472adcfbcea862881ef6c9e90670a17135","sha256:0bc96a456455b4a55c458ed2959f78d9cf596c84c0504cc101772594da55726d"],"state_sha256":"0274cfec7ef5e5ea774fe3325318cbfb9e5c3d43a4cfae67d8dc25f31241e4fa"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Q/t53OEeJ+C2vG9dvYm+RvzvrgjVcp3WQ5D3NBaRK1Zm/hc/ZCIFHEoV1sRp+CDsFWGk5sdiO7CSmguzR8g+CQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-19T16:23:34.182487Z","bundle_sha256":"34197252ad81c125909aa4641bca63a5c4673ef3d14b37f89a5342627fdcb238"}}