%I #14 May 13 2013 01:54:18
%S 2,4,10,74,146,256,440,470,584,920,1070,1156,1324,1394,1420,2080,2470,
%T 2600,3326,3746,4796,5996,6460,7160,7466,8894,9164,9554,9596,10490,
%U 10970,11204,11246,11336,11374,12314,12386,13394,14290,15586,16250,16330,17060
%N n^2 + {1,3,7} are primes.
%C Under Schinzel's hypothesis H, this sequence is infinite. - _Charles R Greathouse IV_, Apr 23 2012
%H Charles R Greathouse IV, <a href="/A182238/b182238.txt">Table of n, a(n) for n = 1..10000</a>
%e 2^2+{1,3,7}= {5,7,11} all prime, 4^2+{1,3,7}= {17,19,23} all prime.
%o (PARI)
%o { forstep ( n=2, 10^6, 2,
%o ns = n * n;
%o if ( ! isprime( ns+1 ), next() );
%o if ( ! isprime( ns+3 ), next() );
%o if ( ! isprime( ns+7 ), next() );
%o print1(n, ", ");
%o ); }
%o /* _Joerg Arndt_, Apr 22 2012 */
%Y Intersection of A005574, A049422, A114270.
%K nonn
%O 1,1
%A _Zak Seidov_, Apr 20 2012