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A176682
Numbers k such that k^2 +-7 are primes.
5
6, 12, 18, 36, 48, 60, 66, 132, 138, 162, 186, 192, 216, 228, 270, 330, 360, 366, 408, 468, 474, 582, 606, 642, 678, 708, 744, 792, 1086, 1182, 1236, 1308, 1326, 1458, 1524, 1686, 1782, 1902, 1998, 2040, 2124, 2178, 2208, 2244, 2358, 2370, 2634, 2658, 2760
OFFSET
1,1
LINKS
EXAMPLE
12 is in the sequence, because 12^2 - 7 = 137 and 12^2 + 7 = 151 are primes.
MATHEMATICA
Select[Range[8! ], PrimeQ[ #^2-7]&&PrimeQ[ #^2+7]&]
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved