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%I #8 Feb 18 2018 10:03:28
%S 3,7,17,23,41,47,71,89,103,113,127,137,151,191,193,199,223,263,271,
%T 281,337,359,401,439,457,503,521,569,577,599,641,719,727,751,839,857,
%U 863,881,887,929,991,1009,1033,1097,1103,1151,1193,1217,1231,1279,1297,1303
%N Primes p such that (p^2+7)/8 is prime.
%C For all primes q>2, we have q=4k+-1 for some k, which makes it easy to show that 8 divides q^2+7.
%t Select[Prime[Range[200]],PrimeQ[(#^2+7)/8]&]
%o (PARI) lista(nn) = {forprime(p=2, nn, iferr(if (isprime(q=(p^2+7)/8), print1(q, ", ")), E, ););} \\ _Michel Marcus_, Feb 18 2018
%Y Similar sequences, with p and (p^2+a)/b both prime, are A048161, A062324, A062326, A062718, A109953, A110589, A118915, A118918, A118939, A118941 and A118942.
%K nonn
%O 1,1
%A _T. D. Noe_, May 06 2006
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