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Israel Journal of Mathematics

, Volume 77, Issue 3, pp 345–348 | Cite as

On exactlym times covers

  • Zhi-Wei Sun
Article

Abstract

In this paper it is shown that if every integer is covered bya 1+n 1ℤ,…,a k +n k ℤ exactlym times then for eachn=1,…,m there exist at least ( n m ) subsetsI of {1,…k} such that ∑ i I 1/n i equalsn. The bound ( n m ) is best possible.

Keywords

Lower Bound Group Theory Number Theory Surprising Result Unsolved Problem 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Hebrew University 1992

Authors and Affiliations

  • Zhi-Wei Sun
    • 1
  1. 1.Department of MathematicsNanjing UniversityNanjingPeople’s Republic of China

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