Cauchy-Davenport theorem
If and are non-empty subsets of , then
where denotes the sumset of and .
References
- 1 Melvyn B. Nathanson. Additive Number Theory: Inverse Problems and Geometry ofSumsets, volume 165 of GTM. Springer, 1996. http://www.emis.de/cgi-bin/zmen/ZMATH/en/quick.html?type=html&an=0859.11003Zbl 0859.11003.