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Primes p of the form k^2 + 1 such that p+2 and 2p+1 are also prime.
1

%I #27 Oct 21 2022 06:59:53

%S 5,25601,193601,1144901,1464101,4326401,6100901,12390401,23522501,

%T 72931601,127012901,245862401,256960901,351937601,441840401,732784901,

%U 802588901,951722501,1621672901,2024100101,2070250001,2217468101,2219352101,2428518401,2930056901,2963713601

%N Primes p of the form k^2 + 1 such that p+2 and 2p+1 are also prime.

%C All primes (except 5) in the sequence are of the form 100*k^2 + 1.

%t Select[Range[50000]^2 + 1, AllTrue[{#, # + 2, 2*# + 1}, PrimeQ] &] (* _Amiram Eldar_, Sep 20 2021 *)

%Y Intersection of A002496 and A045536.

%K nonn

%O 1,1

%A _Angad Singh_, Sep 20 2021