Abstract
Higman showed that if A is any language then SUBSEQ(A) is regular. His proof was nonconstructive. We show that the result cannot be made constructive. In particular we show that if f takes as input an index e of a total Turing Machine M e , and outputs a DFA for SUBSEQ(L(M e )), then ∅″≤T f (f is Σ 2-hard). We also study the complexity of going from A to SUBSEQ(A) for several representations of A and SUBSEQ(A).
Similar content being viewed by others
References
Beigel, R.: Query-limited reducibilities. PhD thesis, Stanford University (1987). Also available as Report No. STAN-CS-88-1221
Beigel, R.: Unbounded searching algorithms. SIAM J. Comput. 19(3), 522–537 (1990)
Beigel, R., Gasarch, W.: On the complexity of finding the chromatic number of a recursive graph, II: the unbounded case. Ann. Pure Appl. Log. 45(3), 227–246 (1989)
Beigel, R., Gasarch, W., Gill, J., Owings, J.: Terse, superterse, and verbose sets. Inf. Comput. 103(1), 68–85 (1993)
Bentley, J.L., Yao, A.C.-C.: An almost optimal algorithm for unbounded searching. Inf. Process. Lett. 5(3), 82–87 (1976)
Blum, L., Blum, M.: Towards a mathematical theory of inductive inference. Inf. Comput. 28, 125–155 (1975)
Case, J., Smith, C.H.: Comparison of identification criteria for machine inductive inference. Theor. Comput. Sci. 25, 193–220 (1983)
Ershov, Y.L., Goncharov, S.S., Nerode, A., Remmel, J.B. (eds): Handbook of Recursive Mathematics, vol. 1: Recursive Model Theory, vol. 2: Recursive Algebra, Analysis, and Combinatorics. Elsevier, New York (1998)
Fahmy, A.F., Roos, R.: Efficient learning of real time one-counter automata. In: Proceedings of the 6th International Workshop on Algorithmic Learning Theory ALT’95. Lecture Notes in Computer Science, vol. 997, pp. 25–40. Springer, Berlin (1995)
Fenner, S., Gasarch, W.: The complexity of learning SUBSEQ(A). In: Proceedings of the 17th International Conference on Algorithmic Learning Theory. Lecture Notes in Artificial Intelligence, vol. 4264, pp. 109–123. Springer, Berlin (2006).
Fischer, P.C.: Turing machines with restricted memory access. Inf. Control 9, 364–379 (1966)
Fischer, P.C., Meyer, A.R., Rosenberg, A.L.: Counter machines and counter languages. Math. Syst. Theory 2(3), 265–283 (1968)
Gasarch, W., Guimarães, K.S.: Binary search and recursive graph problems. Theor. Comput. Sci. 181, 119–139 (1997)
Gasarch, W., Martin, G.: Bounded Queries in Recursion Theory. Progress in Computer Science and Applied Logic. Birkhäuser, Boston (1999)
Gold, E.M.: Language identification in the limit. Inf. Comput. 10(10), 447–474 (1967)
Hartmanis, J.: Context-free languages and Turing machine computations. In: Schwartz, J.T. (ed.) Proceedings of Symposia in Applied Mathematics. Mathematical Aspects of Computer Science, vol. 19, pp. 42–51. American Mathematical Society, Providence (1967)
Hartmanis, J.: On the succinctness of different representations of languages. SIAM J. Comput. 9 (1980)
Hay, L.: On the recursion-theoretic complexity of relative succinctness of representations of languages. Inf. Control 52 (1982)
Higman, A.G.: Ordering by divisibility in abstract algebras. Proc. Lond. Math. Soc. 3, 326–336 (1952)
Metakides, G., Nerode, A.: Effective content of field theory. Ann. Math. Log. 17, 289–320 (1979)
Minsky, M.L.: Recursive unsolvability of post’s problem of “Tag”. Ann. Math. 74(3), 437–453 (1961)
Muchnik, A.A.: On strong and weak reducibility of algorithmic problems. Sib. Mat. Zh. 4, 1328–1341 (1963) (in Russian)
Simpson, S.G.: Subsystems of Second Order Arithmetic. Perspectives in Mathematical Logic Series. Springer, Berlin (1999)
Simpson, S.G. (ed.): Reverse Mathematics 2001. Perspectives in Mathematical Logic Series. Association of Symbolic Logic (2005)
Sipser, M.: Introduction to the Theory of Computation, 2nd edn. Course Technology, Inc. (2005)
Soare, R.I.: Recursively Enumerable Sets and Degrees. Perspectives in Mathematical Logic. Springer, Berlin (1987)
Soare, R.I.: Computability and recursion. Bull. Symb. Log. 27 (1996)
Valiant, L.G., Paterson, M.S.: Deterministic one-counter automata. J. Comput. Syst. Sci. 10, 340–350 (1975)
van Leeuwen, J.: Effective constructions in well-partially-ordered free monoids. Discrete Math. 21, 237–252 (1978)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Fenner, S., Gasarch, W. & Postow, B. The Complexity of Finding SUBSEQ(A). Theory Comput Syst 45, 577–612 (2009). https://doi.org/10.1007/s00224-008-9111-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00224-008-9111-4