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%I #9 Dec 19 2014 04:36:06
%S 419,617,827,1097,1187,1229,1487,1531,1609,1669,1811,2143,2243,2251,
%T 2311,2539,2677,2693,2707,2713,2819,2953,3203,3221,3539
%N Starting primes for which there is only one solution in A097231.
%e a(1) = 419 because there is only one 3 X 3 square arrangement of the primes 419, 421, 431, 433, 439, 443, 449, 457 and 461 such that all row, column and diagonal totals are primes. Here is the unique solution for the starting prime 419:
%e ......+-----+-----+-----+
%e ......|.421.|.439.|.431.|. --> .1291
%e ......+-----+-----+-----+
%e ......|.449.|.419.|.433.|. --> .1301
%e ......+-----+-----+-----+
%e ......|.457.|.461.|.443.|. --> .1361
%e ......+-----+-----+-----+
%e ...../..vvv...vvv...vvv..\
%e ..1301..1327..1319..1307..1283
%Y Cf. A097231 (number of distinct solutions for each starting prime), A097232 (starting primes with no solutions).
%K nonn
%O 1,1
%A Chuck Seggelin (seqfan(AT)plastereddragon.com), Jul 31 2004
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