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%I #16 Sep 08 2022 08:45:11
%S 1,3,15,33,45,57,117,147,243,255,303,375,423,447,453,477,573,753,837,
%T 897,903,1035,1497,1905,2055,2085,2193,2283,2433,2487,2535,2583,2757,
%U 2823,2943,2955,3003,3213,3285,3345,3603,3657,3687,4407,4575,4977,5037,5043,5325,5355,5367,5403,5727
%N Numbers n such that p=n^2+2 and p+2 are primes.
%C 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
%H M. F. Hasler, <a href="/A086381/b086381.txt">Table of n, a(n) for n = 1..10000</a>
%F Intersection of A067201 and A007591. - _M. F. Hasler_, Jan 19 2015
%o (Magma)[n: n in [0..10000]|IsPrime(n^2+2) and IsPrime(n^2+4)] // _Vincenzo Librandi_, Dec 16 2010
%o (PARI) is_A086381(x)=ispseudoprime(x^2+2)&&ispseudoprime(x^2+4)
%o forstep(x=1,9999,2,is_A086381(x)&&print1(x",")) \\ _M. F. Hasler_, Jan 16 2015
%Y Cf. A253639, A085554, A059100, A087475.
%K easy,nonn
%O 1,2
%A _Zak Seidov_, Sep 07 2003
%E More terms from _Vincenzo Librandi_, Dec 16 2010
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