221:). A simpler proof of this based on left-sets was given by Ogihara and Watanabe in 1991. Mahaney's argument does not actually require the sparse language to be in NP (because the existence of an NP-hard sparse set implies the existence of an NP-complete sparse set), so there is a sparse
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Jin-Yi Cai. Lecture 11: P=poly, Sparse Sets, and
Mahaney's Theorem. CS 810: Introduction to Complexity Theory. The University of Wisconsin–Madison. September 18, 2003 (PDF)
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M. Ogiwara and O. Watanabe. On polynomial time bounded truth-table reducibility of NP sets to sparse sets.
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In 1999, Jin-Yi Cai and D. Sivakumar, building on work by
Ogihara, showed that if there exists a sparse
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are sparse. An example of a nontrivial sparse language is the set of binary strings containing exactly
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Juris
Hartmanis, Neil Immerman, Vivian Sewelson. Sparse Sets in NP-P: EXPTIME versus NEXPTIME.
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Jin-Yi Cai and D. Sivakumar. Sparse hard sets for P: resolution of a conjecture of
Hartmanis.
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S. R. Mahaney. Sparse complete sets for NP: Solution of a conjecture by Berman and
Hartmanis.
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311:{\displaystyle {\textbf {NP}}\subseteq {\textbf {P}}/{\text{poly}}}
202:. Mahaney used this to show in 1982 that if any sparse language is
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Balcázar, JosĂ© Luis; DĂaz, Josep; GabarrĂł, Joaquim (1990).
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274:-complete language to a sparse language if and only if
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Fortune showed in 1979 that if any sparse language is
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69:because there are a total of 2 strings of length
251:if and only if there exist sparse languages in
138:strings in the language, which is bounded by
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367:S. Fortune. A note on sparse complete sets.
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439:, volume 65, issue 2/3, pp.158–181. 1985.
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146:Relationships to other complexity classes
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77:that it contains rapidly goes to zero as
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453:Journal of Computer and System Sciences
382:Journal of Computer and System Sciences
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371:, volume 8, issue 3, pp.431–433. 1979.
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58:of all sparse languages is called
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40:in the language, is bounded by a
493:Sparse Sets (Tribute to Mahaney)
270:from Mahaney's theorem) from an
176:polynomial-time Turing reduction
525:Computational complexity theory
130:{\displaystyle {\binom {n}{k}}}
18:computational complexity theory
167:Although not all languages in
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483:Favorite Theorems: Small Sets
397:volume 20, pp.471–483. 1991.
65:Sparse languages are called
182:/poly to a sparse language.
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395:SIAM Journal on Computing
369:SIAM Journal on Computing
409:Structural Complexity II
54:with other classes. The
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174:are sparse, there is a
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89:1 bits for some fixed
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266:(as opposed to the
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34:complexity function
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485:. April 18, 2006.
384:25:130–143. 1982.
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520:Formal languages
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514:Categories
345:References
42:polynomial
28:(a set of
461:0022-0000
326:-complete
289:⊆
239:Further,
217:(this is
207:-complete
190:-complete
154:contains
413:Springer
209:, then
192:, then
30:strings
505:SPARSE
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152:SPARSE
67:sparse
60:SPARSE
226:-hard
188:co-NP
172:/poly
156:TALLY
24:is a
457:ISSN
417:ISBN
305:poly
20:, a
16:In
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334:=
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253:NP
248:NE
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331:L
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