Each of the letters represent a different integer 0 TO 9 and each row and each column represent a nine digit prime number (18 in all).

C D A E I H D I C
B C C C A C D B F
B G H G D A H J D
F G E C B C A D A
I A D B J F E F C
A G I G F C A B D
D D I G E E A D A
F E E C F E H A C
C D C F D A F D F

I used a short program to test for primality, thus this was all done "almost" by hand.

A, C, D and F are the final digits of prime numbers, so they must be odd, and not 5.

Checking all combinations of values, there are two possibilities: ACDF=3179 or 9137.

Checking now BCCCACDBF, in both cases B=6.

Going on to CBBFIADFC, I=2 or I=5.

Trying out IBJDFBDAD, we have three cases: ABCDFIJ=3617920, 3617925, or 3617952.

Moving on to AGIGFCABD, we can have ABCDFGIJ=36179025 or 36179852.

Now with BGHGDAHJD, we have ABCDFGHIJ=361790825 or 361798052.

Finally, checking FGECBCADA, the only possibility is ABCDEFGHIJ=3617490825.
Edited on August 24, 2004, 8:27 am

Posted by Oskar on 2004-08-24 08:26:21