Product-Free Lambek Calculus Is NP-Complete

In this paper we prove that the derivability problems for productfree Lambek calculus and product-free Lambek calculus allowing empty premises are NP-complete. Also we introduce a new derivability characterization for these calculi.

• Type: Conference
• Year: 2009
• Where: LFCS
• Authors: Yury Savateev
• Keywords: Artificial Intelligence, Lambek Calculus, LFCS 2009, Product-free Lambek Calculus, Productfree Lambek Calculus