IBM Research | Ponder This | May 2002 solutions
Skip to main content

May 2002

<<April May June>>

1)Center=(31.25,0), radius=31.25, points (0,0), (2,11), (2,-11), (40,30), (40,-30), (50,25), (50,-25)

Schinzel's theorem guarantees that this problem can be solved for any given number of lattice points.

2)The smallest such circle has center (5/22,9/22) and radius sqrt(276250)/22.

3)Vladimir Sedach and Hajo Luers each submitted a list of 65 circles with radius less than 50, each passing through exactly seven lattice points.

If you have any problems you think we might enjoy, please send them in. All replies should be sent to: