Questions tagged [functional-completeness]

For questions regarding functionally complete sets of Boolean functions, that is, logical connectives.

6 questions
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proof of functional completeness of logical operators

If I know that the set of operators {∨, & , ¬} is functionally complete, how do I go about proving/disproving the functional completeness of the following set of operators? a) $\{\vee,\neg\}$ b) $\{\to,\neg\}$ c) $\{\to\}$ I have looked at the…
3
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1 answer

How the two derived identities help prove that the 2-basis ensures $\mathtt{NAND}$'s functional completeness?

I am proving that $\mathtt{NAND}$ is functionally complete in Boolean algebra using Robert Veroff’s 2-basis for the Sheffer stroke ($\mathtt{NAND}$) from his paper (A Shortest 2-Basis for Boolean Algebra in Terms of the Sheffer Stroke). I need…
3
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1 answer

Proof-Theoretic Advantages to Using Only NANDs in Infinitary Logics

This question comes out of a question on Philosophy Stack Exchange, and a particular difference of opinion in regards to the initial question stated in 'Is there any major benefit to using NAND in infinitary logic?'. The question revolves around an…
3
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Showing Functional Completeness

I am reading about Functional Completeness in Wikipedia. In the "Formal Definition: "Since every Boolean function of at least one variable can be expressed in terms of binary Boolean functions, F is functionally complete if and only if every binary…
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Functional completeness of $\{\text{or},\text{ xor}, \text{ xnor}\}$

I need to prove the functional completeness of $\{\text{or},\text{ xor},\text{ xnor}\}$ with the help of $\{\text{not},\text{ or},\text{ and}\}$ (which have been already proven to be functional complete). My attempt is that I only have to show that…
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On the functional-completeness of the Sheffer stroke

I have seen functional-completeness (in regards to boolean functions) defined as: A set X of truth-functions (of 2-valued logic) is functionally complete if and only if for each of the five defined classes, there is a member of X which does not…