首页 | 本学科首页   官方微博 | 高级检索  
     


On set systems with restricted k‐wise L‐intersection modulo a prime,and beyond
Abstract:In this paper, we derive the following bound on the size of a k‐wise L‐intersecting family (resp. cross L‐intersecting families) modulo a prime number:
  • (i) Let p be a prime, urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0001, and urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0002. Let urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0003 and urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0004 be two disjoint subsets of urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0005 such that urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0006, or urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0007. Suppose that urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0008 is a family of subsets of [n] such that urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0009 for every urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0010 and urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0011 for every collection urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0012 of k distinct subsets in urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0013. Then, urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0014 This result may be considered as a modular version of Theorem 1.10 in [J. Q. Liu, S. G. Zhang, S. C. Li, H. H. Zhang, Eur. J. Combin. 58 (2016), 166‐180].
  • (ii) Let p be a prime, urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0015, and urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0016. Let urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0017 and urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0018 be two subsets of urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0019 such that urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0020, or urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0021, or urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0022. Suppose that urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0023 and urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0024 are two families of subsets of [n] such that (1) urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0025 for every pair urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0026; (2) urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0027 for every urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0028; (3) urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0029 for every urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0030. Then, urn:x-wiley:10638539:media:jcd21604:jcd21604-math-0031
This result extends the well‐known Alon–Babai–Suzuki theorem to two cross L‐intersecting families.
Keywords:Alon –  Babai–  Suzuki theorem  Erdő  s–  Ko–  Rado theorem  Frankl–  Wilson theorem  Grolmusz–  Sudakov theorem  05D05  11F75  11B05
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号