文摘
For two finite sets of integers and their additive energy is the number of solutions to , where and . Given finite sets with additive energy , we investigate the sizes of largest subsets and with all sums , , being different (we call such subsets co-Sidon). In particular, for we show that in the case of small energy, , one can always find two co-Sidon subsets with sizes , whenever satisfy . An example showing that this is best possible up to the logarithmic factor is presented. When the energy is large, , we show that there exist co-Sidon subsets of with sizes whenever satisfy and show that this is best possible. These results are extended (non-optimally, however) to the full range of values of .