In this note we prove that, if Sn is the greatest area of a rectangle
which can be covered with n unit disks, then 2≤Sn/n<33/2, and
these are the best constants; moreover, for Δ(n):=(33/2)n−Sn, we
have 0.727384<liminfΔ(n)/n<2.121321 and
0.727384<limsupΔ(n)/n<4.165064.Comment: 8 pages, 3 figures, some corrections made in version