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Marrero on characterization of pseudo $(v,\\, k,\\, \\la)$-designs are obtained."},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"0905.2740","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.CO","submitted_at":"2009-05-17T14:00:46Z","cross_cats_sorted":[],"title_canon_sha256":"df2af752b6dc5fbd8340e5099bd97eb2a7179dbdc058844d68de9b8c8cb7eeef","abstract_canon_sha256":"d8eaedaa787a16fb013fcf66eef588eee7faceda49e20740f2ce3f46c0eae563"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:08:24.753021Z","signature_b64":"BqWYVapTs3V8EGsQgOzAoLMuk3wEdCTNNQv7OpYpKoSIJudefnD11ZHN9tl5RBrD/W5lYyNtLYfsAO4NfL24CA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1f6020abd26e4ae3ca95874e9c9074fca116d1e335a1fba9c13b714fc34683ba","last_reissued_at":"2026-05-18T04:08:24.752529Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:08:24.752529Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Bipartite graphs with five eigenvalues and pseudo designs","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"math.CO","authors_text":"Ebrahim Ghorbani","submitted_at":"2009-05-17T14:00:46Z","abstract_excerpt":"A pseudo $(v,\\, k,\\, \\la)$-design is a pair $(X, {\\cal B})$ where $X$ is a $v$-set and ${\\cal B}=\\{B_1,...,B_{v-1}\\}$ is a collection of $k$-subsets (blocks) of $X$ such that each two distinct $B_i, B_j$ intersect in $\\la$ elements; and $0\\le\\la <k \\le v-1$. 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