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 A086172 #15 Sep 08 2022 08:45:11 %S A086172 1,2,4,6,24,30,36,42,72,84,98,100,116,126,128,144,162,174,206,212,228, %T A086172 288,312,318,324,336,350,360,406,408,416,418,452,458,466,498,510,522, %U A086172 528,530,536,546,548,556,604,654,660,666,682,684,690,708,710,728,738 %N A086172 Numbers n such that n*prime(n)+1 is prime. %C A086172 See also A086173, A086174, A086175, A086176, A086177. %H A086172 Vincenzo Librandi, <a href="/A086172/b086172.txt">Table of n, a(n) for n = 1..1000</a> %t A086172 Select[Range[1000], PrimeQ[ # Prime[ # ]+1]&] %o A086172 (Magma) [n: n in [1..800] | IsPrime(n*NthPrime(n) + 1)]; // _Vincenzo Librandi_, Oct 05 2012 %o A086172 (PARI) is(n,p=prime(n))=isprime(n*p+1) \\ _Charles R Greathouse IV_, Feb 17 2017 %Y A086172 Cf. A086173, A086174, A086175, A086176, A086177. %K A086172 easy,nonn %O A086172 1,2 %A A086172 _Zak Seidov_, Jul 11 2003