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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..25.

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: A292422 A328497 A138062 * A233551 A142281 A242281

Adjacent sequences:  A097230 A097231 A097232 * A097234 A097235 A097236

KEYWORD

nonn

AUTHOR

Chuck Seggelin (seqfan(AT)plastereddragon.com), Jul 31 2004

STATUS

approved

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Last modified July 12 22:46 EDT 2020. Contains 335669 sequences. (Running on oeis4.)