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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.

A155703 Primes p such that 2*p^2 + 16*p + 23 is also prime.

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%I A155703 #17 Jun 30 2025 14:15:45
%S A155703 3,7,13,19,31,43,97,127,223,241,271,283,307,397,421,439,577,601,619,
%T A155703 661,673,691,727,853,859,967,1009,1051,1063,1123,1153,1237,1321,1429,
%U A155703 1447,1543,1567,1597,1609,1657,1669,1861,1867,1933,1951,1987,2017,2089,2203
%N A155703 Primes p such that 2*p^2 + 16*p + 23 is also prime.
%H A155703 Vincenzo Librandi, <a href="/A155703/b155703.txt">Table of n, a(n) for n = 1..1000</a>
%t A155703 Select[Prime[Range[2500]], PrimeQ[(2*#^2 + 16*# + 23)]&] (* _Vincenzo Librandi_, Oct 30 2012 *)
%o A155703 (Magma) [p: p in PrimesUpTo(3000)|IsPrime(2*p^2+16*p+23)];
%Y A155703 Cf. A155702, A153037.
%K A155703 nonn,easy
%O A155703 1,1
%A A155703 _Vincenzo Librandi_, Jan 25 2009
%E A155703 Entries confirmed by _John W. Layman_, Jun 17 2010