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 A070156 #15 Jun 21 2024 06:38:41
%S A070156 4,6,180,3390,18060,19380,34500,92220,92640,96180,114660,127680,
%T A070156 133980,140760,159630,161880,172170,207480,254280,255840,263820,
%U A070156 296910,309780,378570,380880,397590,408690,422880,432660,440550,511170,540390,572940
%N A070156 Numbers k such that k-1, k+1, k^2+1 and k^4+1 are all prime numbers.
%H A070156 Amiram Eldar, <a href="/A070156/b070156.txt">Table of n, a(n) for n = 1..10000</a>
%e A070156 For n = 6: 5, 7, 37, 1297 are all primes.
%t A070156 Do[s=n; If[PrimeQ[n-1]&&PrimeQ[n+1]&&PrimeQ[1+n^2] &&PrimeQ[1+n^4], Print[n]], {n, 1, 1000000}]
%o A070156 (PARI) is(k) = isprime(k-1) && isprime(k+1) && isprime(k^2+1) && isprime(k^4+1); \\ _Amiram Eldar_, Jun 21 2024
%Y A070156 Subsequence of A070155.
%Y A070156 Cf. A001359.
%K A070156 easy,nonn
%O A070156 1,1
%A A070156 _Labos Elemer_, Apr 23 2002
%E A070156 Offset corrected by _Amiram Eldar_, Jun 21 2024