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A238664 Primes p such that (p+2)^2+2 is prime but (p+1)^2+1 is not prime. 2


%S 7,31,37,43,79,97,103,241,271,307,367,373,421,499,547,571,601,607,709,

%T 751,883,907,967,1033,1129,1213,1231,1237,1327,1423,1597,1609,1621,

%U 1747,1801,1867,1933,1951,1993,2017,2131,2137,2203,2221,2281,2287,2647,2659

%N Primes p such that (p+2)^2+2 is prime but (p+1)^2+1 is not prime.

%H Alois P. Heinz, <a href="/A238664/b238664.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Prime[Range[400]],PrimeQ[(#+2)^2+2]&&CompositeQ[(#+1)^2+1]&] (* _Harvey P. Dale_, Jul 07 2019 *)

%Y Column k=2 of A238086.

%K nonn

%O 1,1

%A _Alois P. Heinz_, Mar 02 2014

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Last modified November 27 09:19 EST 2021. Contains 349365 sequences. (Running on oeis4.)