smallest all-semiprime magic square

[Jonathan Post]

Using A096003 and A097824,  here is the smallest all-semiprime magic square,
which I just discovered today:

============
1139   635   995
 779   923  1067
 851  1211   707
============

In numerical order, these entries are:
635 = 5*127
707 = 7*101
779 = 19*41
851 = 23*37
923 = 13*71
995 = 5*199
1067 = 11*97
1139 = 17*67
1211 = 7*173

As I just noted in a submission to Prime Curios: 2769 is the sum of any row,
column, or diagonal. Curiously, 2769 = 3 * 13 * 71, all three of which are
primes when reversed (but that is too "base" for us here).

Using A096003(16) = 28213, and A097824(16) = 354, one likewise has the
smallest semiprime magic square of order 4.

Using A096003(25) = 2012771, and A097824(25) = 9600, one likewise has the
smallest semiprime magic square of order 5.

I'm not sure if it's better to submit the finite full sequence 1139,  635,
995, 779,  923,  1067,
851,  1211,  707 for the order 3, and similarly for the order 4 and order 5;
or give the sequence of row sums as a function of order n; or what.

I don't know the order 6 or above.

I also know the smallest order 3 of the 3-almost prime magic squares, and so
forth, but these become "less" for most seqfans, I suspect.

I admit to not yet having written down the smallest semiprime magic cbe, but
the same method can be adapted...

This is, new, is it not?

Happy Hanukkah, Merry Christmas, etcetera,

-- Jonathan Vos Post
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