Derivate des Benzo[1.3]dioxols, 47 [1]. Darstellung und Reaktionen des 4.8-Dimethoxy-bis[1.3]dioxolo[4.5]benzo- [1.2-d; 1′ .2′ -f] [1.3]dioxepins / Derivatives of 1,3-Benzodioxoles, 47 [1]. Preparation and Reactions of 4,8-Dimethoxy-bis[1,3]dioxolo[4,5]benzo- [1,2-d; 1',2'-f][1,3]dioxepine [PDF]
Zeitschrift für Naturforschung B, 1983 Abstract In 1957 some dibenzo[d,f][1,3]dioxepines were isolated from Cercospora kikuchii. We describe the preparation of 4,8-dimethoxy-bis[1,3]dioxolo[4,5]benzo[1,2-d; 1',2'-f][1,3]-dioxepine (3). It shows a high SE-reactivity. Bromination yields the monobromo-and dibromocompounds 3 a and 3 b.
Franz Dallacker, Wim Coerver
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Perfect Matching in Random Graphs is as Hard as Tseitin [PDF]
TheoretiCS, 2022 We study the complexity of proving that a sparse random regular graph on an odd number of vertices does not have a perfect matching, and related problems involving each vertex being matched some pre-specified number of times.
Per Austrin, Kilian Risse
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Tameness and the power of programs over monoids in DA [PDF]
Logical Methods in Computer Science, 2022 The program-over-monoid model of computation originates with Barrington's proof that the model captures the complexity class $\mathsf{NC^1}$. Here we make progress in understanding the subtleties of the model.
Nathan Grosshans +2 more
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Characterization theorem for the conditionally computable real functions [PDF]
Logical Methods in Computer Science, 2017 The class of uniformly computable real functions with respect to a small subrecursive class of operators computes the elementary functions of calculus, restricted to compact subsets of their domains.
Ivan Georgiev
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Point-Separable Classes of Simple Computable Planar Curves [PDF]
Logical Methods in Computer Science, 2012 In mathematics curves are typically defined as the images of continuous real functions (parametrizations) defined on a closed interval. They can also be defined as connected one-dimensional compact subsets of points.
Xizhong Zheng, Robert Rettinger
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First-order query evaluation on structures of bounded degree [PDF]
Logical Methods in Computer Science, 2011 We consider the enumeration problem of first-order queries over structures of bounded degree. It was shown that this problem is in the Constant-Delaylin class. An enumeration problem belongs to Constant-Delaylin if for an input of size n it can be solved
Wojciech Kazana, Luc Segoufin
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A note on first-order spectra with binary relations [PDF]
Logical Methods in Computer Science, 2018 The spectrum of a first-order sentence is the set of the cardinalities of its finite models. In this paper, we consider the spectra of sentences over binary relations that use at least three variables.
Eryk Kopczynski, Tony Tan
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Relating Functional and Imperative Session Types [PDF]
Logical Methods in Computer Science, 2022 Imperative session types provide an imperative interface to session-typed communication. In such an interface, channel references are first-class objects with operations that change the typestate of the channel.
Hannes Saffrich, Peter Thiemann
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The Wadge Hierarchy of Deterministic Tree Languages [PDF]
Logical Methods in Computer Science, 2008 We provide a complete description of the Wadge hierarchy for deterministically recognisable sets of infinite trees. In particular we give an elementary procedure to decide if one deterministic tree language is continuously reducible to another.
Filip Murlak
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A Model of Cooperative Threads [PDF]
Logical Methods in Computer Science, 2010 We develop a model of concurrent imperative programming with threads. We focus on a small imperative language with cooperative threads which execute without interruption until they terminate or explicitly yield control.
Martín Abadi, Gordon D. Plotkin
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