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.
%I A127435 #17 Jul 21 2025 00:26:29
%S A127435 2,3,5,7,11,17,37,41,67,127,131,151,157,181,211,241,251,257,271,281,
%T A127435 307,397,401,421,431,467,491,557,571,577,647,691,701,751,761,827,907,
%U A127435 911,937,947,967,1061,1097,1151,1277,1291,1307,1321,1367,1567,1571,1861
%N A127435 Primes p such that (p-1)^2 + 1 is prime.
%C A127435 Consists of 3 and a subsequence of A045349.
%C A127435 These are the primes of the form A067720(k)+1. - _Michel Marcus_, Nov 21 2020
%H A127435 Vincenzo Librandi, <a href="/A127435/b127435.txt">Table of n, a(n) for n = 1..2289</a>
%F A127435 a(n) = sqrt(A127436(n)-1) + 1.
%t A127435 Select[Prime@Range[300], PrimeQ[(# - 1)^2 + 1] &] (* _Ray Chandler_, Jan 23 2007 *)
%o A127435 (PARI) listp(nn) = {forprime(p=2, nn, if (isprime((p-1)^2 + 1), print1(p, ", ")););} \\ _Michel Marcus_, Jun 08 2016
%o A127435 (Magma) [p: p in PrimesUpTo(2000) | IsPrime((p^2-2*p+2))]; // _Vincenzo Librandi_, Jul 20 2025
%Y A127435 For the associated primes, see A127436.
%Y A127435 Cf. A045349, A067720.
%K A127435 nonn
%O A127435 1,1
%A A127435 _Lekraj Beedassy_, Jan 14 2007
%E A127435 Corrected and extended by _Ray Chandler_, Jan 23 2007