Permanent problem IDPPL 038
Additive combinatorics
Determine the sharp lower-density behavior possible for infinite Sidon sets, including whether the known density barriers can be attained or improved.
Determine the sharp lower-density behavior possible for infinite Sidon sets, including whether the known density barriers can be attained or improved.
A solution must appear in a reputable journal, with documentation that Erdős offered the displayed amount. Claims are administered by the Combinatorics Foundation; erdosproblems.com does not pay awards.