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A086381
Numbers n such that p=n^2+2 and p+2 are primes.
11
1, 3, 15, 33, 45, 57, 117, 147, 243, 255, 303, 375, 423, 447, 453, 477, 573, 753, 837, 897, 903, 1035, 1497, 1905, 2055, 2085, 2193, 2283, 2433, 2487, 2535, 2583, 2757, 2823, 2943, 2955, 3003, 3213, 3285, 3345, 3603, 3657, 3687, 4407, 4575, 4977, 5037, 5043, 5325, 5355, 5367, 5403, 5727
OFFSET
1,2
COMMENTS
The twin primes are given by A253639 and A085554. Except for the initial term, all a(n)=3 (mod 6). - M. F. Hasler, Jan 16 2015
LINKS
FORMULA
Intersection of A067201 and A007591. - M. F. Hasler, Jan 19 2015
PROG
(Magma)[n: n in [0..10000]|IsPrime(n^2+2) and IsPrime(n^2+4)] // Vincenzo Librandi, Dec 16 2010
(PARI) is_A086381(x)=ispseudoprime(x^2+2)&&ispseudoprime(x^2+4)
forstep(x=1, 9999, 2, is_A086381(x)&&print1(x", ")) \\ M. F. Hasler, Jan 16 2015
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Zak Seidov, Sep 07 2003
EXTENSIONS
More terms from Vincenzo Librandi, Dec 16 2010
STATUS
approved