Zhu's algebra, C_2-algebra and C_2-cofiniteness of parafermion vertex   operator algebras
  We determine Zhu's algebra and C_2-algebra of parafermion vertex operator algebras for sl_2. Moreover, we prove the C_2-cofiniteness of parafermion vertex operator algebras for any finite dimensional simple Lie algebras. 
Tomoyuki Arakawa, Ching Hung Lam, Hiromichi Yamada
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