Hypergraphs and Degrees of Parallelism: A Completeness Result
نویسندگان
چکیده
In order to study relative PCF-definability of boolean functions, we associate a hypergraph Hf to any boolean function f (following [2, 4]). We introduce the notion of timed hypergraph morphism and show that it is: – Sound: if there exists a timed morphism from Hf to Hg then f is PCF-definable relatively to g. – Complete for subsequential functions: if f is PCF-definable relatively to g, and g is subsequential, then there exists a timed morphism from Hf to Hg.
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