A Type of 4-isosceles Set with 6-point
Xianglin Wei · 2004
Let P be a finite planar set. P is called a k-isosceles for k≥3,if every k-point subset of P contains a point equidistant from two others.Fishburn raised a problem that whether there exists a 4-isosceles 6-point with no 4-point on a circle and no 3-point on a line.The existences of 4-isosceles 6-point set with no 4-point on a circle and 4-isosceles 6-point set with no 4-point on a circle and no 3-point on a line are proved.