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(Again copied verbatim from a September 2009 thread I made.)

A Primally Magic Square (PMS) is exactly like a traditional magic square with a change of criteria. Where a traditional magic square is one where the sum of each row, column, and both diagonals are some number, usually 15 (uses 1-9). By contrast, a PMS is one where all rows, columns, and both diagonals form a prime number. Note: if a number is prime either forward or back, it counts.

Example:

$\displaystyle \begin{matrix} 1 & 3 & 7 \\ 3 & 9 & 7 \\ 7 & 7 & 9 \end{matrix}$

137, 397, 977, 797, and 199 are all prime, so this square is a PMS.

How many 3x3 PMS's are there?

How many 4x4 PMS's are there?

How many 5x5 PMS's are there?

How many 9x9 PMS's are there?

Side note: Feel free to calculate the number of PMS's for some other $n$.

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    @Jacob: Nice links! Those are not quite what I'm going for here though; my condition is merely that each column, row, and diagonal needs to be prime in at least one direction, not both as they did.2011-05-18

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