The number of (2,3)-sum-free subsets of { 1,...,n}
نویسندگان
چکیده
منابع مشابه
The number of maximal sum-free subsets of integers
Cameron and Erdős [6] raised the question of how many maximal sum-free sets there are in {1, . . . , n}, giving a lower bound of 2bn/4c. In this paper we prove that there are in fact at most 2(1/4+o(1))n maximal sum-free sets in {1, . . . , n}. Our proof makes use of container and removal lemmas of Green [8, 9] as well as a result of Deshouillers, Freiman, Sós and Temkin [7] on the structure of...
متن کاملdetermination of maximal singularity free zones in the workspace of parallel manipulator
due to the limiting workspace of parallel manipulator and regarding to finding the trajectory planning of singularity free at workspace is difficult, so finding a best solution that can develop a technique to determine the singularity-free zones in the workspace of parallel manipulators is highly important. in this thesis a simple and new technique are presented to determine the maximal singula...
15 صفحه اولThe unit sum number of discrete modules
In this paper, we show that every element of a discrete module is a sum of two units if and only if its endomorphism ring has no factor ring isomorphic to $Z_{2}$. We also characterize unit sum number equal to two for the endomorphism ring of quasi-discrete modules with finite exchange property.
متن کاملThe unit sum number of Baer rings
In this paper we prove that each element of any regular Baer ring is a sum of two units if no factor ring of R is isomorphic to Z_2 and we characterize regular Baer rings with unit sum numbers $omega$ and $infty$. Then as an application, we discuss the unit sum number of some classes of group rings.
متن کاملGeneralized Sum - Free Subsets 751
Let F {A(1): < i < t, t 2}, be a finite collection of finite, palrwlse disjoint subsets of Z+. Let SC R\{0} and A Z+ be finite sets. Denote by S A {i=isi:a A, i S, the s i are not ncesarily dlstinct }. For S and F as above we say that S is F-free if for every A(i), A(J) F, i J, SA(1)(% SA(j) . We prove that for S and F as above, S contains an F-free subset Q such that This result generalizes ea...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Acta Arithmetica
سال: 2001
ISSN: 0065-1036,1730-6264
DOI: 10.4064/aa98-2-6