login
A097233
Starting primes for which there is only one solution in A097231.
2
419, 617, 827, 1097, 1187, 1229, 1487, 1531, 1609, 1669, 1811, 2143, 2243, 2251, 2311, 2539, 2677, 2693, 2707, 2713, 2819, 2953, 3203, 3221, 3539
OFFSET
1,1
EXAMPLE
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:
......+-----+-----+-----+
......|.421.|.439.|.431.|. --> .1291
......+-----+-----+-----+
......|.449.|.419.|.433.|. --> .1301
......+-----+-----+-----+
......|.457.|.461.|.443.|. --> .1361
......+-----+-----+-----+
...../..vvv...vvv...vvv..\
..1301..1327..1319..1307..1283
CROSSREFS
Cf. A097231 (number of distinct solutions for each starting prime), A097232 (starting primes with no solutions).
Sequence in context: A328497 A138062 A350781 * A233551 A142281 A242281
KEYWORD
nonn
AUTHOR
Chuck Seggelin (seqfan(AT)plastereddragon.com), Jul 31 2004
STATUS
approved