{"id":"openai-math/Constant-factor-hardness-of-directed-feedback-vertex-set","pdf":"https://github.com/openai/math/blob/main/preprints/Constant-factor-hardness-of-directed-feedback-vertex-set-September-23-2026/paper.pdf","url":"https://github.com/openai/math/tree/main/preprints/Constant-factor-hardness-of-directed-feedback-vertex-set-September-23-2026","tags":["computational-complexity","approximation-algorithms","graph-theory"],"score":0,"title":"Constant-factor hardness of directed feedback vertex set","domain":"Theoretical computer science","family":"102","origin":"ai-generated","source":"openai-math","authors":["OpenAI"],"reviews":0,"subject":"cs.CC","summary":"Approximating minimum directed feedback vertex set within any fixed constant factor is NP-hard, even on unweighted digraphs.","category":"research","comments":0,"disputed":false,"division":"cs","mentions":0,"discussed":0,"published":"2026-09-23","reactions":{},"formalized":false,"family_title":"The Unique Games Conjecture and optimal approximation thresholds"}