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  1. Jeremy Avigad, Ulrich W. Kohlenbach, Henry Towsner, Samson Abramsky, Andreas Blass, Larry Moss, Alf Onshuus Nino, Patrick Speissegger, Juris Steprans & Monica VanDieren (2012). New Orleans Marriott and Sheraton New Orleans Hotels New Orleans, LA January 8–9, 2011. Bulletin of Symbolic Logic 18 (1).
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  2. Arnon Avron, Oskar Becker, Johan van Benthem, Andreas Blass, Robert Brandom, L. E. J. Brouwer, Donald Davidson, Michael Dummett, Walter Felscher & Kit Fine (2009). Jagadeesan, Radha, 306 Japaridze, Giorgi, Xi. In Ondrej Majer, Ahti-Veikko Pietarinen & Tero Tulenheimo (eds.), Games: Unifying Logic, Language, and Philosophy. Springer Verlag. 377.
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  3. Andreas Blass, Nachum Dershowitz & Yuri Gurevich (2009). When Are Two Algorithms the Same? Bulletin of Symbolic Logic 15 (2):145-168.
    People usually regard algorithms as more abstract than the programs that implement them. The natural way to formalize this idea is that algorithms are equivalence classes of programs with respect to a suitable equivalence relation. We argue that no such equivalence relation exists.
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  4. Andreas Blass, Su Gao & Yi Zhang (2009). Preface. Annals of Pure and Applied Logic 158 (3):155.
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  5. Michael Benedikt, Andreas Blass, Natasha Dobrinen, Noam Greenberg, Denis R. Hirschfeldt, Salma Kuhlmann, Hannes Leitgeb, William J. Mitchell & Thomas Wilke (2007). Gainesville, Florida March 10–13, 2007. Bulletin of Symbolic Logic 13 (3).
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  6. David Blair, Andreas Blass & Paul Howard (2005). Divisibility of Dedekind Finite Sets. Journal of Mathematical Logic 5 (01):49-85.
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  7. Andreas Blass (2005). Howard Paul and Rubin Jean E.. Consequences of the Axiom of Choice, Mathematical Surveys and Monographs, Vol. 59. American Mathematical Society, Providence, RI, 1998, Viii+ 432 Pp. [REVIEW] Bulletin of Symbolic Logic 11 (1):61-63.
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  8. P. Howard, J. E. Rubin & Andreas Blass (2005). REVIEWS-Consequences of the Axiom of Choice. Bulletin of Symbolic Logic 11 (1):61-62.
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  9. Andreas Blass & Yuri Gurevich (2003). Strong Extension Axioms and Shelah's Zero-One Law for Choiceless Polynomial Time. Journal of Symbolic Logic 68 (1):65-131.
    This paper developed from Shelah's proof of a zero-one law for the complexity class "choice-less polynomial time." defined by Shelah and the authors. We present a detailed proof of Shelah's result for graphs, and describe the extent of its generalizability to other sorts of structures. The extension axioms, which form the basis for earlier zero-one laws (for first-order logic, fixed-point logic, and finite-variable infinitary logic) are inadequate in the case of choiceless polynomial time; they must be replaced by what we (...)
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  10. Andreas Blass & Victor Pambuccian (2003). Sperner Spaces and First‐Order Logic. Mathematical Logic Quarterly 49 (2):111-114.
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  11. Andreas Blass, Yuri Gurevich & Saharon Shelah (2002). On Polynomial Time Computation Over Unordered Structures. Journal of Symbolic Logic 67 (3):1093-1125.
    This paper is motivated by the question whether there exists a logic capturing polynomial time computation over unordered structures. We consider several algorithmic problems near the border of the known, logically defined complexity classes contained in polynomial time. We show that fixpoint logic plus counting is stronger than might be expected, in that it can express the existence of a complete matching in a bipartite graph. We revisit the known examples that separate polynomial time from fixpoint plus counting. We show (...)
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  12. Andreas Blass (2001). Needed Reals and Recursion in Generic Reals. Annals of Pure and Applied Logic 109 (1-2):77-88.
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  13. Andreas Blass, Yuri Gurevich & Saharon Shelah (2001). Addendum to “Choiceless Polynomial Time”. Annals of Pure and Applied Logic 112 (1):117.
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  14. Andreas Blass, Yuri Gurevich & Saharon Shelah (2001). Addendum to “Choiceless Polynomial Time”: Ann. Pure Appl. Logic 100 (1999) 141–187. Annals of Pure and Applied Logic 112 (1):117.
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  15. Andreas Blass & Yuri Gurevich (2000). The Logic of Choice. Journal of Symbolic Logic 65 (3):1264-1310.
    The choice construct (choose x: φ(x)) is useful in software specifications. We study extensions of first-order logic with the choice construct. We prove some results about Hilbert's ε operator, but in the main part of the paper we consider the case when all choices are independent.
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  16. Andreas Blass, Yuri Gurevich & Saharon Shelah (1999). Choiceless Polynomial Time. Annals of Pure and Applied Logic 100 (1-3):141-187.
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  17. Andreas Blass & Heike Mildenberger (1999). On the Cofinality of Ultrapowers. Journal of Symbolic Logic 64 (2):727-736.
    We prove some restrictions on the possible cofinalities of ultrapowers of the natural numbers with respect to ultrafilters on the natural numbers. The restrictions involve three cardinal characteristics of the continuum, the splitting number s, the unsplitting number r, and the groupwise density number g. We also prove some related results for reduced powers with respect to filters other than ultrafilters.
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  18. Andreas Blass (1995). An Induction Principle and Pigeonhole Principles for K-Finite Sets. Journal of Symbolic Logic 60 (4):1186-1193.
    We establish a course-of-values induction principle for K-finite sets in intuitionistic type theory. Using this principle, we prove a pigeonhole principle conjectured by Bénabou and Loiseau. We also comment on some variants of this pigeonhole principle.
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  19. Andreas Blass (1995). Questions and Answers–a Category Arising in Linear Logic, Complexity Theory, and Set Theory. In Jean-Yves Girard, Yves Lafont & Laurent Regnier (eds.), Advances in Linear Logic. Cambridge University Press. 222--61.
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  20. Andreas Blass (1993). Review: Michael Makkai, Robert Pare, Accessible Categories: The Foundations of Categorical Model Theory. [REVIEW] Journal of Symbolic Logic 58 (1):355-357.
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  21. Andreas Blass (1992). A Game Semantics for Linear Logic. Annals of Pure and Applied Logic 56 (1-3):183-220.
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  22. Andreas Blass (1992). Review: W. Hugh Woodin, A. S. Kechris, D. A. Martin, Y. N. Moschavokis, Ad and the Uniqueness of the Supercompact Measures on $Pomega1 (Lambda)$; W. Hugh Woodin, Some Consistency Results in ZFC Using AD; Alexander S. Kechris, D. A. Martin, J. R. Steel, Subsets of $Aleph1$ Constructible From a Real. [REVIEW] Journal of Symbolic Logic 57 (1):259-261.
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  23. Andreas Blass (1992). Woodin W. Hugh. AD and the Uniqueness of the Supercompact Measures on Pω1 (Λ). Cabal Seminar 79–81, Proceedings, Caltech-UCLA Logic Seminar 1979–81, Edited by Kechris AS, Martin DA, and Moschavokis YN, Lecture Notes in Mathematics, Vol. 1019, Springer-Verlag, Berlin Etc. 1983, Pp. 67–71. Woodin W. Hugh. Some Consistency Results in ZFC Using AD. Cabal Seminar 79–81, Proceedings, Caltech-UCLA Logic Seminar 1979–81, Edited by Kechris AS, Martin DA, and Moschavokis YN, Lecture Notes in Mathematics, Vol ... [REVIEW] Journal of Symbolic Logic 57 (1):259-261.
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  24. Andreas Blass & Andre Scedrov (1992). Complete Topoi Representing Models of Set Theory. Annals of Pure and Applied Logic 57 (1):1-26.
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  25. Andreas Blass (1990). Groupwise Density and Related Cardinals. Archive for Mathematical Logic 30 (1):1-11.
    We prove several theorems about the cardinal $\mathfrak{g}$ associated with groupwise density. With respect to a natural ordering of families of nond-ecreasing maps fromω toω, all families of size $< \mathfrak{g}$ are below all unbounded families. With respect to a natural ordering of filters onω, all filters generated by $< \mathfrak{g}$ sets are below all non-feeble filters. If $\mathfrak{u}< \mathfrak{g}$ then $\mathfrak{b}< \mathfrak{u}$ and $\mathfrak{g} = \mathfrak{d} = \mathfrak{c}$ . (The definitions of these cardinals are recalled in the introduction.) Finally, (...)
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  26. Andreas Blass (1990). Infinitary Combinatorics and Modal Logic. Journal of Symbolic Logic 55 (2):761-778.
    We show that the modal propositional logic G, originally introduced to describe the modality "it is provable that", is also sound for various interpretations using filters on ordinal numbers, for example the end-segment filters, the club filters, or the ineffable filters. We also prove that G is complete for the interpretation using end-segment filters. In the case of club filters, we show that G is complete if Jensen's principle □ κ holds for all $\kappa ; on the other hand, it (...)
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  27. Andreas Blass (1990). Review: Marcia J. Groszek, Applications of Iterated Perfect Set Forcing. [REVIEW] Journal of Symbolic Logic 55 (1):360-361.
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  28. Andreas Blass & Claude Laflamme (1989). Consistency Results About Filters and the Number of Inequivalent Growth Types. Journal of Symbolic Logic 54 (1):50-56.
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  29. Andreas Blass & Jacob Plotkin (1989). Meeting of the Association for Symbolic Logic, East Lansing, Michigan, 1988. Journal of Symbolic Logic 54 (2):674-677.
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  30. Andreas Blass & Saharon Shelah (1989). Near Coherence of Filters. III. A Simplified Consistency Proof. Notre Dame Journal of Formal Logic 30 (4):530-538.
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  31. Andreas Blass (1988). Selective Ultrafilters and Homogeneity. Annals of Pure and Applied Logic 38 (3):215-255.
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  32. Andreas Blass & Saharon Shelah (1987). There May Be Simple and and the Rudin-Keisler Ordering May Be Downward Directed. Annals of Pure and Applied Logic 33:213-243.
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  33. Andreas Blass & Saharon Shelah (1987). There May Be Simple Pℵ1 and Pℵ2-Points and the Rudin-Keisler Ordering May Be Downward Directed. Annals of Pure and Applied Logic 33:213-243.
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  34. Andreas Blass (1986). Near Coherence of Filters. I. Cofinal Equivalence of Models of Arithmetic. Notre Dame Journal of Formal Logic 27 (4):579-591.
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  35. Andreas Blass, Louise Hay & Peter G. Hinman (1986). Meeting of the Association for Symbolic Logic: Chicago, 1985. Journal of Symbolic Logic 51 (2):507-510.
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  36. Andreas Blass & Andre Scedrov (1986). Small Decidable Sheaves. Journal of Symbolic Logic 51 (3):726-731.
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  37. Andreas Blass (1985). Acknowledgement of Priority. Journal of Symbolic Logic 50 (3):781.
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  38. Andreas Blass (1984). There Are Not Exactly Five Objects. Journal of Symbolic Logic 49 (2):467-469.
    We exhibit a Horn sentence expressing the statement of the title; the construction generalizes to arbitrary primes in place of five.
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  39. Andreas Blass (1981). Some Initial Segments of the Rudin-Keisler Ordering. Journal of Symbolic Logic 46 (1):147-157.
    A 2-affable ultrafilter has only finitely many predecessors in the Rudin-Keisler ordering of isomorphism classes of ultrafilters over the natural numbers. If the continuum hypothesis is true, then there is an ℵ 1 -sequence of ultrafilters D α such that the strict Rudin-Keisler predecessors of D α are precisely the isomorphs of the D β 's for $\beta.
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  40. Andreas Blass (1981). The Model of Set Theory Generated by Countably Many Generic Reals. Journal of Symbolic Logic 46 (4):732-752.
    Adjoin, to a countable standard model M of Zermelo-Fraenkel set theory (ZF), a countable set A of independent Cohen generic reals. If one attempts to construct the model generated over M by these reals (not necessarily containing A as an element) as the intersection of all standard models that include M ∪ A, the resulting model fails to satisfy the power set axiom, although it does satisfy all the other ZF axioms. Thus, there is no smallest ZF model including M (...)
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  41. Andreas Blass (1977). Amalgamation of Nonstandard Models of Arithmetic. Journal of Symbolic Logic 42 (3):372-386.
    Any two models of arithmetic can be jointly embedded in a third with any prescribed isomorphic submodels as intersection and any prescribed relative ordering of the skies above the intersection. Corollaries include some known and some new theorems about ultrafilters on the natural numbers, for example that every ultrafilter with the "4 to 3" weak Ramsey partition property is a P-point. We also give examples showing that ultrafilters with the "5 to 4" partition property need not be P-points and that (...)
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  42. Andreas Blass (1977). Ramsey's Theorem in the Hierarchy of Choice Principles. Journal of Symbolic Logic 42 (3):387-390.
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  43. Andreas Blass (1976). Review: W. W. Comfort, S. Negrepontis, The Theory of Ultrafilters. [REVIEW] Journal of Symbolic Logic 41 (4):782-783.
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  44. J. T. Baldwin & Andreas Blass (1974). An Axiomatic Approach to Rank in Model Theory. Annals of Mathematical Logic 7 (2-3):295-324.
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  45. Andreas Blass (1974). On Certain Types and Models for Arithmetic. Journal of Symbolic Logic 39 (1):151-162.
    There is an analogy between concepts such as end-extension types and minimal types in the model theory of Peano arithmetic and concepts such as P-points and selective ultrafilters in the theory of ultrafilters on N. Using the notion of conservative extensions of models, we prove some theorems clarifying the relation between these pairs of analogous concepts. We also use the analogy to obtain some model-theoretic results with techniques originally used in ultrafilter theory. These results assert that every countable nonstandard model (...)
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  46. Andreas Blass & Douglas Cenzer (1974). Cores of Π11 Sets of Reals. Journal of Symbolic Logic 39 (4):649 - 654.
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  47. Andreas Blass (1972). On the Inadequacy of Inner Models. Journal of Symbolic Logic 37 (3):569-571.
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  48. Andreas Blass (1972). The Intersection of Nonstandard Models of Arithmetic. Journal of Symbolic Logic 37 (1):103-106.
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  49. Andreas Blass (1972). Theories Without Countable Models. Journal of Symbolic Logic 37 (3):562-568.
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