A260352 - OEIS

%I #12 Sep 08 2022 08:46:13

%S 0,1,2,3,4,5,6,7,8,9,15,18,19,23,28,29,30,41,42,49,62,69,70,94,95,108,

%T 123,136,145,151,152,189,190,204,212,215,223,227,276,277,278,281,290,

%U 291,294,314,328,342,353,367,368,372,405,410,436,488,497

%N Numbers n such that both 2*n^2+11 and 2*(n+1)^2+11 are prime.

%C Both n and n+1 are terms in A092968.

%H Zak Seidov, <a href="/A260352/b260352.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[0, 600], PrimeQ[2 #^2 + 11] &&  PrimeQ[2 (# + 1)^2 + 11] &] (* _Vincenzo Librandi_, Jul 26 2015 *)

%o (PARI) isok(n) = isprime(2*n^2+11) && isprime(2*(n+1)^2+11); \\ _Michel Marcus_, Jul 26 2015

%o (Magma) [n: n in [0..600]| IsPrime( 2*n^2+11) and IsPrime(2*(n+1)^2+11)]; // _Vincenzo Librandi_, Jul 26 2015

%Y Cf. A092968.

%K nonn,easy

%O 1,3

%A _Zak Seidov_, Jul 23 2015