\input zb-basic
\input zb-matheduc
\iteman{ZMATH 1996a.00451}
\itemau{Beck, I.; Bejlegaard, N.; Erd\"os P.; Fishburn, P.}
\itemti{Equal distance sums in the plane.}
\itemso{Normat 43, No. 4, 150-161 (1995).}
\itemab
An equisum set in the plane is a finite set X$_n$ of distinct points $\lbrack{}$x$_1, x_2$, ..., $x_n\rbrack{}$ such that the sum of the distances from x$_i$ to all of the other points in X is the same for all i = 1, 2, ..., n. The authors show that an equisum set in which all the interpoint distances are different must have at least 5 elements. They also investigate the possible numbers of different interpoint distances in an equisum set with 5 elements.
\itemrv{~}
\itemcc{G45}
\itemut{}
\itemli{}
\end