Problem A. 638. (March 2015)
A. 638. Does there exist a simple, closed polyline in the 3dimensional Cartesian coordinate system whose perpendicular projection onto every coordinate plane is a cycleless graph?
Proposed by: Imre Leader, Cambridge
(5 pont)
Deadline expired on 10 April 2015.
Statistics:
3 students sent a solution.  
5 points:  Williams Kada. 
0 point:  2 students. 
