Ed Pegg Jr. writes:

<<
Joe Kisenwether has upped the ante.  Arrange the numbers 1-32 in a circle so
that any two adjacent numbers sum to a square number.  The answer is unique.
>>

That's an interesting circle.  I'd like to see a picture of the circle of numbers 1-32 in numerical order, with 32 chords indicating adjacency in the Kisenwether ordering -- especially with that ordering being unique.

--Dan