New Fixed Point Combinators from Old

Jan Willem Klop
Vrije Universiteit Amsterdam


There are two themes in this note. The first is how to derive new fixed point combinators from given ones. Here we extend the derivation principle leading to the Böhm sequence of fpc's. The second is the question how to prove that the new fpc's are indeed new. More general, we tentatively present a method to discriminate terms as to beta-convertability that goed beyond the classical Böhm-out technique, and exploits the clock behaviour that is inherent in a lambda-term.

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