smallest all-semiprime magic square

[Jonathan Post]

Has progress been made since this article?

Magic Tesseracts
Ivars Peterson
http://www.sciencenews.org/pages/sn_arc99/10_16_99/mathland.htm

The smallest perfect magic tesseract is or order 16 (i.e. 16 x 16 x 16 x
16).

Are there prime magic tesseracts known? Can we construct semiprime magic
tesseracts analogous to the semiprime magic squares discussed earlier?

Does the Peter Loly result on moment of intertia of magic squares and magic
cubes extend to magic tesseracts, with modifications since 4-D rotation is
about a plane rather than about an axis?

On 12/24/06, David Wilson <davidwwilson at comcast.net> wrote:
>
>  Oh wait, I just had a "duh" moment.
>
> For a 3x3 magic square with center entry k, the row sum is 3k. So for a
> 3x3 prime magic square, the row sum is 3*prime, for a semiprime magic
> square, the row sum is 3*semiprime, for a parition number magic square, the
> row sum is 3*partition number, etc.
>
> Thus the 3x3 semiprime magic square cannot have a semiprime sum.
>
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