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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A154408 Primes p such that (p^2 + 1)/10 is also prime.

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%I A154408 #12 Sep 08 2022 08:45:40
%S A154408 7,13,17,23,37,53,67,97,103,113,127,137,163,167,197,223,227,263,277,
%T A154408 283,347,367,373,383,397,433,503,547,587,617,653,673,677,683,773,797,
%U A154408 823,877,883,937,947,953,997,1063,1103,1117,1163,1187,1213,1367,1423,1447
%N A154408 Primes p such that (p^2 + 1)/10 is also prime.
%H A154408 Vincenzo Librandi, <a href="/A154408/b154408.txt">Table of n, a(n) for n = 1..1000</a>
%e A154408 37 is in the sequence because both 37 and (37^2 + 1)/10 = 137 are primes. [_Emeric Deutsch_, Jan 21 2009]
%p A154408 a := proc (n) if isprime(n) = true and type((1/10)*n^2+1/10, integer) = true and isprime((1/10)*n^2+1/10) = true then n else end if end proc: seq(a(n), n = 2 .. 1700); # _Emeric Deutsch_, Jan 21 2009
%t A154408 Select[Prime[Range[200]], PrimeQ[(#^2 + 1)/10] &] (* _Vincenzo Librandi_, Oct 15 2012 *)
%o A154408 (Magma) [p: p in PrimesInInterval(7, 2500) | IsPrime((p^2 + 1) div 10)]; // _Vincenzo Librandi_, Oct 15 2012
%Y A154408 Cf. A017305.
%K A154408 nonn,easy
%O A154408 1,1
%A A154408 _Vincenzo Librandi_, Jan 09 2009
%E A154408 Corrected and extended by _Emeric Deutsch_, Jan 21 2009