{"paper":{"title":"Unfolding Semantics of the Untyped {\\lambda}-Calculus with letrec","license":"http://creativecommons.org/publicdomain/zero/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.PL","authors_text":"Jan Rochel","submitted_at":"2016-10-19T10:41:32Z","abstract_excerpt":"We investigate the relationship between finite terms in {\\lambda}-letrec, the {\\lambda}-calculus with letrec, and the infinite {\\lambda}-terms they express. We say that a lambda-letrec term expresses a lambda-term if the latter can be obtained as an infinite unfolding of the former. Unfolding is the process of substituting occurrences of function variables by the right-hand side of their definition.\n  We consider the following questions: (i) How can we characterise those infinite {\\lambda}-terms that are {\\lambda}-letrec-expressible? (ii) Given two {\\lambda}-letrec terms, how can we determine "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1610.05954","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"}