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A087697
Numbers k such that k + 7 and k - 7 are both prime.
13
10, 12, 24, 30, 36, 54, 60, 66, 90, 96, 120, 144, 156, 174, 186, 204, 234, 264, 270, 276, 300, 324, 360, 366, 390, 426, 450, 456, 516, 564, 570, 594, 600, 606, 624, 654, 666, 684, 726, 750, 780, 804, 816, 846, 870, 960, 984, 990
OFFSET
1,1
LINKS
MAPLE
select(t -> isprime(t+7) and isprime(t-7), [seq(i, i=8..1000, 2)]); # Robert Israel, Jul 22 2018
MATHEMATICA
Rest[Select[Range[1000], PrimeQ[# - 7] && PrimeQ[# + 7] &]] (* Vincenzo Librandi, Jul 23 2018 *)
PROG
(PARI) isok(n) = isprime(n-7) && isprime(n+7); \\ Michel Marcus, Jul 23 2018
(Magma) [n: n in [5..1000] | IsPrime(n-7) and IsPrime(n+7)]; // Vincenzo Librandi, Jul 23 2018
KEYWORD
nonn,easy
AUTHOR
Zak Seidov, Sep 27 2003
STATUS
approved