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Page 2664 of Mathematical Reviews Vol. , Issue 2001D [page]

2001 Mathematical Reviews  
, Benedetto (I-LAQL-PM; L'Aquila); Varricchio, Stefano (I-ROME2; Rome) On the generalization of Higman and Kruskal’s theorems to regular languages and rational trees.  ...  The main result of the paper is that one can decide whether a rational w-language has as its generator a language with bounded deciphering delay (Theorem 15).  ... 

Well quasi-orders and context-free grammars

Flavio D'Alessandro, Stefano Varricchio
2004 Theoretical Computer Science  
We prove the following generalization of Higman's theorem: any division order on L is a well quasi-order on L.  ...  Let G be a context-free grammar and let L be the language of all the words derived from any variable of G.  ...  In [11] some extensions of Higman and Kruskal's theorem to regular languages and rational trees have been given. Further applications of the wqo theory to formal languages are given in [7, 10] .  ... 
doi:10.1016/j.tcs.2004.03.069 fatcat:hflig35sjrgb5lebglhbvge4oa

Deciding Piecewise Testable Separability for Regular Tree Languages

Jean Goubault-Larrecq, Sylvain Schmitz, Marc Herbstritt
2016 International Colloquium on Automata, Languages and Programming  
We prove a general characterisation of piecewise testable separability on languages in a well-quasiorder, in terms of ideals of the ordering.  ...  A final byproduct is a new proof of the decidability of whether an input regular language of ranked trees is piecewise testable, which was first shown in the unranked case by Bojańczyk, Segoufin, and Straubing  ...  In the same vein, it would be interesting to develop ideal representations for the tree minor ordering, and to try to decide PTL separability for context-free tree languages.  ... 
doi:10.4230/lipics.icalp.2016.97 dblp:conf/icalp/Goubault-Larrecq16 fatcat:6kzs33bamfgvlhuor72x7o4nra

Packing and Covering in Combinatorics

R. A. Cuninghame-Green, A. Schrijver
1980 Journal of the Operational Research Society  
Thus attention is given to the Rogers bound for sphere-packings, Lloyd's theorem on perfect codes, Ramsey's theorem, graphtheoretical results of Konig, Menger, Turan and Tutte, Delsarte's linear programming  ...  We are grateful to the participants of the study week, and to Profes-  ...  This will not cause much loss of generality since, on the one hand, results will be needed often only in their rational form, and, on the other hand, most of the assertions can be straightforwardly extended  ... 
doi:10.2307/2581088 fatcat:szdtpgrkzrfvvehhovqz3r6vxq

Page 1965 of Mathematical Reviews Vol. , Issue Subject Index [page]

Mathematical Reviews  
., (2001f:68014) Intrigila, Benedetto (with Varricchio, Stefano) On the generalization of Higman and Kruskal's theorems to regular languages and rational trees.  ...  ., 2001k:68071 and (2001h:00017) Iwama, Kazuo (with Kambayashi, Yahiko; Takaki, Kazuya) Tight bounds on the number of states of DFAs that are equivalent to n-state NFAs.  ... 

Rewrite Systems [chapter]

1990 Formal Models and Semantics  
W e will have occasion to employ this technique in Sections 4.1 and 8.2. A rewrite system R is terminating for a set of terms T if the rewrite relation !  ...  A ground rewriting-system is one all the rules of which are ground i.e. elements of G G ; an important early paper on ground rewriting is Rosen, 1973 .  ...  The rst author's research w as supported in part by the National Science Foundation under Grant DCR 85-13417, by the Center for Advanced Study of the University of Illinois at Urbana-Champaign, and by  ... 
doi:10.1016/b978-0-444-88074-1.50011-1 fatcat:ep4fhupc75apfkza6x4r6gue2e

Well quasi-order in combinatorics: embeddings and homomorphisms [chapter]

Sophie Huczynska, Nik Ruškuc, Artur Czumaj, Agelos Georgakopoulos, Daniel Kral, Vadim Lozin, Oleg Pikhurko
Surveys in Combinatorics 2015  
The notion of well quasi-order (wqo) from the theory of ordered sets often arises naturally in contexts where one deals with infinite collections of structures which can somehow be compared, and it then  ...  In this article we survey such situations within combinatorics, and attempt to identify promising directions for further research.  ...  A different example of encoding permutations in a class by a regular language, in order to prove rationality of the generating function, can be found in [3] .  ... 
doi:10.1017/cbo9781316106853.009 fatcat:kj5zfvtlevfzrlhgx6hupgt7ve

Page 2044 of Mathematical Reviews Vol. , Issue Author Index [page]

Mathematical Reviews  
(Summary) 2001k:68083 68Q60 Varricchio, Stefano (with Intrigila, Benedetto) On the generalization of Higman and Kruskal’s theorems to regular languages and rational trees.  ...  On the characteristic function of the joint limit distribution of the first and second order power sums. (Russian summary) Teor.  ... 

Page 834 of Mathematical Reviews Vol. , Issue Author Index [page]

Mathematical Reviews  
(Alessandro Berarducci) 2001f:68064 68Q42 (03B35, 68T15, 68W30) — (with Varricchio, Stefano) On the generalization of Higman and Kruskal’s theorems to regular languages and rational trees.  ...  On the global stability, dynamic trade patterns and asset-debt positions of the two country, two good endogenous growth model with adjustment costs of educational investment.  ... 

Symmetry in toric geometry [article]

Lamprini Ananiadi, Universitäts- Und Landesbibliothek Sachsen-Anhalt, Martin-Luther Universität, Thomas Kahle
Based on this, we are able to deduce the combinatorial stabilization of the families of cones of our interest.  ...  The second part of this thesis, Chapter 4, addresses the problem of implicitly computing generating sets of the ideals defining combinatorial objects from statistics called staged trees.  ...  We refer to Kruskal's article [Kru72] for the general theory and to [FT, Theorem 3 .2] for a beautiful proof of the next result. Proposition 1.1.10.  ... 
doi:10.25673/35197 fatcat:fnc6kq4msbekhcufqtmwuqujgy