**Written work –** Due Tuesday, November 15, in class:

Chapter 10 p167: 1, 2, 5, 10, 15

Chapter 10 p167: 25, 28, 30

**WeBWorK –** none

**OpenLab –** none

**Project – **First draft of your group paper is due in class on Thursday, 11/17.

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**Written work –** Due Tuesday, November 15, in class:

Chapter 10 p167: 1, 2, 5, 10, 15

Chapter 10 p167: 25, 28, 30

**WeBWorK –** none

**OpenLab –** none

**Project – **First draft of your group paper is due in class on Thursday, 11/17.

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- Is Kleene's realizability recursive? May 17, 2022Kleene introduced realizability as a practical semantical interpretation of Heyting Arithmetic (see link for definition). The key result he proved is that provability of $\varphi$ in HA implies the existence of a realizer $n \in \mathbb{N}$ for $\varphi$. Two questions: Is $n$ computable from the Gödel code of $\varphi$ (and what if we don't guarantee […]Jori
- Write the truth value of the following statement below May 17, 2022Write the truth value of the following statement: If x/y = 0, then y should not be equal to zero If x > y, then x + 3 < y + 3Krungkrung
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- Undecidibily of the Word Problem for Groups and First Order Logic May 17, 2022I am trying to derive the undecidability of the Word Problem for an arbitrary group, let's call this Problem $WP(G)$. It is clear to me that FOL and higher are undecidable and I want to reduce the $WP(G)$ to a special case of it. For instance if we have a word of length four, we […]Travis
- Semiring homomorphism from RA (sequences) into N (cluster-label) May 17, 2022Hello I m a beginner student of provenance analysis (PA), In PA the idea is: evaluate not just true or false but annotate them by values from some algebraic structure (S,+,•,0,1) (mostly Semirings). The motivation is: get additional additional information beyond truth/falsity about the truth of a statement. I m a beginner and I m […]Tijani Eric van Lessen
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- How do formal proofs work and relate to interpretations? May 16, 2022As far as I know statements in formal logic are written in a (formal) alphabet which are just symbols, where the allowed sentences have to follow certain rules. If they do, they are called well formed. At first however, the elements of the alphabet are just symbols, without deeper meaning. Furthermore one has logical symbols […]user1578232

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